[ Lost in the Landscape ]

seed bomb controversies

Some­one has declared tomor­row, Octo­ber 9, 2010 as Inter­na­tional Tulip Guer­rilla Gar­den­ing Day. [ Here’s the Face­book event. ] I won’t be dis­cussing tulips, but this post does have a few things to say about guer­rilla gardening.

The local native plant list­serv lit up a few weeks ago over a story in the local paper about seed bombs that ran on August 30.

If you’re not up on seed bombs here’s a lit­tle back­ground: The idea of rolling up seeds and clay to make lit­tle balls that could be lobbed into an area to sow the seeds prob­a­bly goes back cen­turies. But the tech­nique was revi­tal­ized in Japan by Masanobu Fukuoka dur­ing the last cen­tury as part of a low-disturbance style of plant­ing. Instead of till­ing the ground, these lumps of seed and clay could be spread out on the earth’s sur­face, reduc­ing ground dis­tur­bance and the result­ing need to weed so intensely. Up to that point the lit­tle round seed deliv­ery devices were known as seed balls, earth balls or even clay dumplings.

With the rise of the mil­i­tant guer­rilla gar­den­ing move­ment, the lit­tle seed ball became one of the weapons of choice against what was per­ceived as urban blight. An untended vacant lot could be show­ered with with these lit­tle pro­jec­tiles, and a few good rains could see the seeds sprout­ing and tak­ing over what might have been inva­sive weeds. In the testosterone-soaked guer­rilla gar­den move­ment the friendly seed ball quickly became rebranded a “seed bomb.”

Now we return to cur­rent times and the arti­cle I started out men­tion­ing: The orig­i­nal cut of the arti­cle touted how these par­tic­u­lar seed bombs con­tained native species, including–cue the scary music–sweet alyssum! While the definitely-not-native sweet alyssum isn’t one of the top two or three most inva­sive plants, it’s undis­put­edly a prob­lem and has no busi­ness in a seed ball that could get hurled into an wild area by a well-meaning guer­rilla gar­dener. In my own gar­den, a sow­ing of the stuff twenty years ago has led to a sit­u­a­tion of seedlings still pop­ping up every time it rains.

The arti­cle gen­er­ated all sorts of com­ments, and sev­eral peo­ple wrote directly to the maker of these par­tic­u­lar seed bombs men­tioned in the paper, Jim Mum­ford of Green­Scaped Build­ings. One thing led to another and it was revealed that the news­pa­per got hold of a bad list of ingre­di­ents, and that sweet alyssum had never been a part of the mix. The news­pa­per ran a side­bar cor­rec­tion to the story. (The species used to me looks like the Cal­i­for­nia native wild­flower mix offered by S&S Seeds.)

Still by that point the dam­age had been done, and the cre­ator of these par­tic­u­lar balls felt like he needed to show up last month at the lion’s den of the the native plant soci­ety meet­ing to do some dam­age con­trol. He brought us all a big bag of free seed balls. He ran down the real list of species that were really in the mix. He reit­er­ated that sweet alyssum had never been part of the mix.

When it was all over, sev­eral in the audi­ence were say­ing they had no trou­ble with the species used to make the seed balls. The plants were all from Cal­i­for­nia and weren’t con­sid­ered inva­sive. But this was a tough crowd to please and there were still a few lin­ger­ing concerns.

Within the state there are dis­tinct forms of many of the plants in the mix, and each region’s flora has a par­tic­u­lar bal­ance of local plants. If you bring in a non-local strain of a “native” plant you might do some­thing to mess up that bal­ance. Really the only way to make a safe seed bomb that you might lob into a wild area would be to use seed from local plants. Seed bombs are fun, but keep them con­fined to urban gar­dens away from wild­lands and don’t go toss­ing the balls into your neigh­bor­hood canyon think­ing you’re doing the earth a favor.

The story of the San Diego seed bombs has a rel­a­tively happy end­ing. But over the last cou­ple of months I’ve run across a seller who offers “West Coast seed bombs” on Etsy and through a num­ber of bou­tiques. The ven­dor lists the ingre­di­ents as “Corn­flower, Siber­ian Wall­flower, Gar­land Chrysan­the­mum, Shasta Daisy, Farewell-to-Spring, Plains Core­op­sis, Sul­phur Cos­mos, Wild Cos­mos, African Daisy, Sweet William, Cal­i­for­nia Poppy, Blan­ket Flower, Baby’s Breath, Tidy Tips, Moun­tain Phlox, Blue Flax, Sweet Alyssum, Annual Lupine, Lemon Mint, Red Poppy, Rocky Moun­tain Pen­ste­mon, Desert Blue­bell, Mex­i­can Hat, Glo­riosa Daisy, None-so-Pretty, Prairie Cone­flower, and Black-eyed Susan.” Not only does this mix include sweet alyssum, it con­tains gar­land chrysan­the­mum, one of our local scourges. Some parts of the coun­try also have prob­lems with the baby’s breath.

The issue of inva­sives aside, it makes me won­der about people’s def­i­n­i­tions of what con­sti­tutes a wild­flower. Siber­ian wall­flower on the West Coast? African daisy?

I got in touch with the mak­ers of these seed bombs, and they were quite respon­sive, say­ing “we are con­tin­u­ally devel­op­ing this prod­uct. Your feed­back will help inform our prod­uct going for­ward and is much appre­ci­ated. We will gladly include infor­ma­tion about the dan­ger of inva­sive species in our prod­uct from here for­ward.” And they asked for sug­ges­tions for plants that would be bet­ter cit­i­zens in a West Coast wild­flower mix. Off the top of my head I referred them to the list accom­pa­ny­ing the arti­cle, and added just a few ideas of Cal­i­for­nia natives not on the list: baby blue eyes, fivespot, coast sun­flower, desert marigold. What oth­ers would you recommend?

If the mak­ers of these seed balls dras­ti­cally change their mix we could have another rel­a­tively happy end­ing. Most of us prob­a­bly have non-native plants in our gar­dens. If what hap­pens in the gar­den stays in the gar­den, then it’s not quite a doom and gloom sce­nario. But we def­i­nitely have a prob­lem if peo­ple start throw­ing seed bombs into the wilds.

In this case, accom­pa­ny­ing the seed balls with a note about the poten­tial threat of inva­sive plants could do as much good as refor­mu­lat­ing the mix.

October 08 2010 | Categories: gardening | Tags: guerrilla gardening • invasive plants • native plants • seed balls • seed bombing | 12 Comments »

a new weed

This past win­ter I was notic­ing a weed pop­ping up all around the yard that I hadn’t noticed before. I was men­tion­ing it to John, and added, “I’m not sure what it is, though think it could be some sort of euphorbia.”

Then in the gen­tly tact­ful way spouses have of cor­rect­ing you and point­ing out your blind spots he qui­etly cleared his throat and pointed to one of the four young pot­ted plants we have around the gar­den of Euphor­bia lam­bii, one of my dry garden-adapted plants from the Canary Islands. “Maybe it’s that?”

Uh, like duh. What else would it be?

Last year was the first that these plants bloomed, and this spring they bloomed with a vengeance. Dur­ing sunny weather over the last few weeks I’ve heard lit­tle pop­ping noises from the direc­tion of the plants, and have come to the con­clu­sion that the sounds were that of seed pods explod­ing and jet­ti­son­ing the dust-like seed every­where.

I may come to regret the day I intro­duced these to the gar­den, which accord­ing to my records is March 9, 2008.

Speak­ing of weedy plants, here’s another sur­prise seedling from the gar­den, a lit­tle baby red foun­tain grass, one of three seedlings I noticed this year. In recent years the related green foun­tain grass, Pen­nise­tum setaceum has become a nox­ious (though stun­ningly beau­ti­ful) weed and has landed high on vir­tu­ally every thou-shalt-not-plant list issued for Cal­i­for­nia. But many peo­ple gave a by to this related red plant. It was often pushed as being ster­ile and inca­pable of repro­duc­ing by seed, a piece of mis­in­for­ma­tion even I relayed in this blog. (I’ve cor­rected that ear­lier oops in case any­one reads that ear­lier post.) As you can see here it can repro­duce by seed, though this form doesn’t spawn the same way reg­u­lar foun­tain grass does. Nor is it imme­di­ately the same mon­ster pest that feather grass (Nas­sella tenuis­sima) can be.

Pok­ing around the web I found an updated plant descrip­tion at San Mar­cos Grow­ers that includes some inter­est­ing back­ground on this plant:

Recent work in prepa­ra­tion for the grass sec­tions of the Flora of North Amer­ica, which will include nat­u­ral­ized and cul­ti­vated grasses, indi­cates that the name cho­sen for this plant will be Pen­nise­tum advena or per­haps P. x advena. Dr. Joseph K. Wipff, pre­vi­ously with Texas A&M and now a tur­f­grass breeder, wrote the sec­tion on Pen­nise­tum and has indi­cated that Red Foun­tain Grass is most likely a cross between P. setaceum and P. macrostachys (AKA ‘Bur­gundy Giant’). As a hybrid the name would most appro­pri­ately be Pen­nise­tum x advena ‘Rubrum’. The latin word advena means “newly arrived” or “stranger.”

So is it safe to plant this form of foun­tain grass? Here’s my think­ing: Hybrids between species are often ster­ile. (Think of mules, the off­spring of a horse and a don­key.) But every now and then some­thing hap­pens that allows the hybrid to repro­duce. Some­times the seedlings will be just as nearly ster­ile as the imme­di­ate par­ent, but other times a muta­tion could ren­der the seedling entirely fer­tile. In that lat­ter sce­nario the nearly-sterile foun­tain grass could turn into some­thing with the ugly inva­sive poten­tial of its Pen­nise­tum setaceum ancestor.

In other words, today I would be cau­tious and not plant it. Unfor­tu­nately, almost twenty years ago, we designed the front yard around a big mound of the stuff. The plants look stun­ning and move gra­ciously in response to the breezes. Their size is per­fect for the spot, and their red color is unmatched among other grasses. Every now and then I look at other options, like those rec­om­mended in the Don’t Plant a Pest brochure put out by the Cal­i­for­nia Inva­sive Plant Coun­cil. But these lists often fall short in the alter­na­tives they offer and end up read­ing like, “Cheese­cake is bad for you. Would you like to eat this deli­cious raw rutabaga instead?” So…I’m still look­ing for the per­fect replace­ment plant–hopefully some sort of native, but in the mean­time I’m pulling the occa­sional seedlings.

June 20 2010 | Categories: gardening • my garden | Tags: Euphorbia lambii • Fountain grass • invasive plants • Pennisetum setaceum 'Rubrum' • weeds | 10 Comments »

plant it once, have it forever

There’s a promi­nent North­ern Cal­i­for­nia nurs­ery* that adver­tises on its web­site that a vari­ety will self-sow and nat­u­ral­ize. Or in its peppy, enthu­si­as­tic way: “Reseeds!” One of the plants so listed has a fol­lowup note: “Due to agri­cul­tural restric­tions, we can­not ship this plant to Arkansas, New Jer­sey, New York, Okla­homa, South Car­olina, and Texas.”

Read between the lines: This plant, under the right con­di­tions, might just run wild, out of con­trol, and take over your gar­den or an ecosys­tem! (Not all plant restric­tions are based on their inva­sive poten­tial, how­ever. For instance, some might be con­trolled because of known pests or dis­eases the species may harbor.)

Over the years I’ve added inter­est­ing plants to the gar­den, only to have them sow and prop­a­gate them­selves all over the gar­den. For most of these, I don’t worry huge amounts that they’ll escape to the nearby wilds because they’re wimps when not pam­pered in a gar­den, but with reg­u­lar water­ing they’re aggres­sive thugs. Pretty thugs, to be sure. But still thugs.

Here are a few of my mis­takes. Some are merely annoy­ing. Oth­ers require mul­ti­ple hours of labor every year to keep under con­trol. Colder areas might not have the same prob­lems with these that I do, but I’m sure you have your own mon­sters. (My apolo­gies in advance to the fine nation of Mex­ico. I just noticed that four of my selec­tions have “Mex­i­can” in their com­mon names…)

Mex­i­can petu­nia (Ruel­lia brit­to­ni­ana). Pretty, tough. Also pretty tough to erad­i­cate in my gar­den once it got a foothold. I should have paid atten­tion when the guy at the plant sale warned me that it might spread. Accord­ing to Flori­data, “Mex­i­can petu­nia is listed as a Cat­e­gory I inva­sive species by the Florida Exotic Pest Plant Coun­cil. This means that it is ‘alter­ing native plant com­mu­ni­ties by dis­plac­ing native species, chang­ing com­mu­nity struc­tures or eco­log­i­cal func­tions, or hybridiz­ing with natives.’ This warn­ing applies to all parts of the state of Florida (and other areas with sim­i­lar mild cli­mates). Where hardy, the Mex­i­can petu­nia excels at invad­ing wet­lands.” It also can be a nui­sance in a dry gar­den like mine where it spreads under­ground and via explod­ing seed pods.

Mex­i­can fan palm (Wash­ing­to­nia robusta). Maybe it’s a uniquely Cal­i­for­nia thing: You go out to the gar­den to pull weeds, and along with the crab­grass and spurge, you end up pulling up lit­tle palm trees. Folks in colder climes might be thrilled to have some of these, but here they’re a nui­sance. Our Mex­i­can fan came with the house, and it took us a few years to finally remove it. All that time we were yank­ing baby palms all over the front yard, and the seed­bank remained viable for sev­eral years afterward.

Mex­i­can feather grass (Nas­sella tenuis­sima). I’ve dinged this plant sev­eral times before. I won’t add any­thing more here other than to note that I’ve prob­a­bly pulled up a hun­dred seedlings this sea­son. At least this is down from the orgy of seedlings that I had when there was a harem of adult plants in the gar­den that appar­ently had noth­ing on their mind except sex and reproduction.

Mex­i­can evening prim­rose (Oenothera species, I think it was O. spe­ciosa). I was on vaca­tion at the Grand Canyon in 1991. Inno­cently I bought a packet of seeds of these that were sold as a “wild­flower.” I was thrilled when they came up the first year and I had a gre­gar­i­ous patch of del­i­cate bright pink flow­ers where there’d been a patch of dirt pre­vi­ously. Lit­tle did I know they’d resow and spread by under­ground run­ners and con­tinue to annoy me to this day. Wild flower, indeed.

Sweet alyssum (Lob­u­laria mar­itima). Don’t let the “sweet” in its com­mon name fool you. I con­tinue to weed alyssum seedlings pop­ping up around the gar­den from a sin­gle packet of mixed col­ors I planted in the late 1980s.

Fort­night lily (Dietes irid­ioides). A few clumps of these came with the house. The tough, hard seeds lay dor­mant in the ground for years and plague you with unwanted seedlings long after you’ve removed their source.

Calla lily (Zant­edeschia aethiopica). I’ll have to admit that I have a soft spot for these plants and don’t pull them out the same way I pull out other unwel­come plants. My parent’s house came with a fifty-foot foun­da­tion plant­ing of them on the north side of their house. The way the plant can spread, how­ever, now makes me think the pre­vi­ous own­ers might have started with just a half dozen plants. Feral callas are plants of con­cern in some Cal­i­for­nia wet­lands. A cou­ple well-watered gar­den spots seem to gen­er­ate calla lilies out of thin air.

Epa­zote (Dys­pha­nia ambro­sioides). I won’t quite call plant­ing this Mex­i­can herb a mis­take, since I use occa­sion­ally in cook­ing. It does spread about the gar­den a bit, how­ever, and pops up in unex­pected places. There are reports [ includ­ing this one ] that it’s col­o­nized parts of New York’s Cen­tral Park–though that’s not my doing. I popped over to Wikipedia and learned this pretty inter­est­ing detail I’d never heard before: “Epa­zote essen­tial oil con­tains ascari­dole…; in pure form, it is an explo­sive sen­si­tive to shock.” Botan­i­cal TNT–Wild!

To my mis­takes, I’ll add some native Cal­i­for­nia annu­als and peren­ni­als that have been really suc­cess­ful in repro­duc­ing them­selves in my gar­den. Cur­rently, my plants are wan­der­ing around an area where they’re desired and haven’t escaped far. I won’t call them mis­takes at this point, but I can see that they could become unwel­come in some situations.

Cal­i­for­nia pop­pies (Escholzia cal­i­for­nica). What? Our sacred state flower?! Well, there are some unwel­come escaped colonies in Chile and Aus­tralia. And the seeds reg­u­larly find their way into cracks in the pavement.

Baby blue eyes (Nemophila men­ziesii). Not really what I’d call a thug, though these seem to be pretty suc­cess­ful at repro­duc­ing them­selves. It’s easy to pull out the occa­sional unwanted plants, but who’d want to?

Clarkia (Clarkia spp.). I haven’t grown many clarkia species, but the one that seems to wan­der around the most for me is C. rubi­cunda ssp. blas­dalei.

*There’s a good chance you’ll have guessed the iden­tity of this well-known nurs­ery if you’ve spent any time at its web­site. I don’t mean to diss them at all. You can get poten­tially ram­bunc­tious plants from vir­tu­ally all nurs­eries, includ­ing those ded­i­cated to native plants.

April 03 2010 | Categories: gardening • my garden | Tags: invasive plants • seed-grown plants • weeds | 10 Comments »

our gardens after we’re gone

Ever won­der what your gar­den would look like if the human care­tak­ers just vanished?

Maybe I’ve been inspired by all the dis­as­ter flicks like 2012 or the His­tory Channel’s Life After Peo­ple series. But envi­sion­ing gar­dens after gar­den­ers is an inter­est­ing intel­lec­tual exer­cise that might help us answer that pesky ques­tion: What is a garden?

Would all the inva­sive species take over? Would the native plants reclaim their turf? For how long would you still be able to tell that a gar­den existed in a spot in the first place?

I looked at parts of my back yard and tried to imag­ine what would happen.

Within the first month, in South­ern California’s dry cli­mate, most of the pot­ted plants would per­ish for lack of water. Some of the suc­cu­lents might hang on longer, but with­out an exten­sive root sys­tem in the ground, they’d be doomed.

This lit­tle frog would be star­ing at a bog gar­den where all the bog plants have died back, once again for lack of water.

Within two or three months the fish­ponds would be dry: no waterlilies, no cat­tails, no sedges, no water for the local birds.

This pathetic patch of grass would go through boom and bust cycles, turn­ing green with the rains, dying back to brown other times of year. Seeds of other plants bet­ter adapted to the con­di­tions would even­tu­ally take hold. Maybe some plants from the local canyon. Maybe some hardy exotic or inva­sive species.

Behind the back fence of the house is this slope dom­i­nated by ram­pant ice­plant. The the neigh­bor behind me and I haven’t been able agree on what to do with the space. I’ve planted a small col­lec­tion of native plants to help sta­bi­lize the slope. These are species that with only once excep­tion can be found within a five mile radius of the house, and include plants like this night­shade, Solanum parishii…

…and Del Mar Man­zanita, Arc­tostaphy­los glan­du­losa ssp. cras­si­fo­lia, an extremely rare plant that’s on the Fed­eral endan­gered species list. The neigh­bor, how­ever, loves their ice­plant and can’t imag­ine of a slope with­out this gaw­daw­ful inva­sive species clam­or­ing all over it. The local chap­ter of the Cal­i­for­nia Native Plant Soci­ety has pre­pared a great pam­phlet on get­ting rid of ice­plant that you can view [ here ]. It goes into some great rea­sons to get rid of the stuff:

Planted on hill­sides of thou­sands of homes in San Diego, it has since crawled off the orig­i­nal site and into neigh­bor­ing Open Space parks, endan­ger­ing unique plants by smoth­er­ing them. Ice­plant pro­vides lit­tle habi­tat value com­pared to the plant com­mu­nity that it is replac­ing. Com­pared to the native shrubs, ice­plant has very shal­low roots that do not hold soil well; close inspec­tion often reveals gul­lies under­neath the twisted mat of vines. After rain, Ice­plant engorges with water, sub­stan­tially increas­ing its weight. As a result, ice­plant can cause the dete­ri­o­ra­tion of steep hill­sides by encour­ag­ing slump­ing – poten­tially endan­ger­ing the house above.

For peo­ple in sub­ur­bia, “habi­tat value” might mean plants that har­bor scary wild ani­mals and bugs, so that’s not always the most com­pelling rea­son to go native. The fact that ice­plant might endan­ger their prop­erty val­ues could be more persuasive.

So, return­ing to my main topic, the ice­plant would prob­a­bly over­run most of the native plants in a very few years and form a deep pile. Once we neglected the slope for a few years and found that the mat of ice­plant was start­ing to push the back fence over. Within ten years the fence would begin to fail and the ice­plant would begin its descent into the lower garden.

These plants along the back fence would stand a chance of sur­viv­ing with­out water. The yucca, palm, pro­tea would be tall enough to sur­vive an onslaught of maraud­ing ice­plant from behind. They’re plants that don’t require much main­te­nance, and this wall of foliage would prob­a­bly look unchanged for a num­ber of years. But the lower aloes and other suc­cu­lents would likely be smoth­ered by the iceplant.

This apri­cot against the back fence never looks great with­out sum­mer water­ing, but it sur­vives. It’s tall enough that it would prob­a­bly sur­vive the ice­plant inva­sion. Some of the adja­cent native plants do great with the nat­ural con­di­tions. They might not cope so well with the maraud­ing iceplant.

The neigh­bor on the side has Alger­ian ivy that requires con­stant clip­ping to keep it next door. Within two years it would begin to estab­lish itself in the back yard. Taller plants that might sur­vive the ice­plant inva­sion might have ivy crawl­ing up and smoth­er­ing them.

This raised bed near the house is where veg­gies and irri­gated plants live. Most of the exotic plants wouldn’t make it with­out water. The Dr. Hurd man­zanita, the bougainvil­lea vine and maybe the Gar­rya ellip­tica would prob­a­bly hang in there, how­ever, maybe for decades, maybe for much longer.

Fifty to seventy-five years out the house would start to fail. Plants might begin to move in. The sur­round­ing gar­den space would be over­grown with the hardi­est drought-adapted species. I almost never plant in rows, but the mixed ori­gins of the species–South Africa, South Amer­ica, Europe, as well as from all over Cal­i­for­nia, not just local species–would clue an inves­ti­ga­tor into the fact that a gar­den existed on the site. The rela­tion­ships between the plants would be dic­tated by nature, not a gar­dener pre­serv­ing order between plants with mis­matched lev­els of vigor.

Chances are excel­lent that one hun­dred years out, maybe two hun­dred or more, the most per­sis­tent inva­sive species would still be here. Ice­plant and ivy, plus fen­nel and black mus­tard that have invaded the local canyons, would fea­ture in the neigh­bor­hood land­scape. But while many inva­sives bask in the newly dis­turbed earth of a gar­den or the re-engineered grades around roads, they don’t always do so well long-term. Biol­o­gists have sug­gested that many native plants would return to a place where they’re not being pulled out or con­stantly mowed. My yard might be col­o­nized by the local Mex­i­can elder­berry, or toyon, or lemon­ade berry, or prickly pear. And maybe some of the plants I’ve already intro­duced to the yard will per­sist and repro­duce. The restora­tion of nature might spread from my house and from the wild edges of nature just a few houses away.

Even after nature returns, the occa­sional hardy exotic plant sur­viv­ing amidst the natives, along with some of the neighborhood’s plant­i­ngs of trees and shrubs in rows will make it obvi­ous: There used to be gar­dens here.

February 02 2010 | Categories: gardening • landscape | Tags: drought-tolerant landscaping • iceplant • invasive plants • native plants | 26 Comments »

out with the old

This will be the year that I finally win the bat­tle against Mex­i­can feath­er­grass, the blog­ger said opti­misti­cally. I doubt that I’ll be see­ing the end of this beau­ti­ful but wildly over­pro­lific grass any time soon, but I’ve com­pleted pulling all the par­ent plants in the gar­den. With the source of seeds removed, the hun­dreds of unwanted seedlings that I have to pull up every year should diminish.

So how bad was the feath­er­grass prob­lem? Here’s a shot under­neath a black sage in the back yard, no closer than seventy-five feet from the near­est adult feath­er­grass plant capa­ble of set­ting seed. The seed just blew down­wind and set up house­hold in the shel­tered ger­mi­nat­ing con­di­tions in the shade of the sage. Other areas of the gar­den will look like this when the rains begin again and all the banked seed begins to ger­mi­nate. I hate to think that these might get to the local urban canyon, four houses away.

My rela­tion­ship with Mex­i­can feath­er­grass (Nas­sella tenuis­sima or Stipa tenuis­sima) started off in the early 1990s. Like most peo­ple who’ve planted it, I saw it at the nurs­ery with its stalks weav­ing del­i­cately in its beguil­ing come-hither way and fell in love. I bought two.

At first things between us went well. The grasses spread a bit, but the thought of free plants were a real bonus. I even gave plants away.

Though pro­lific, the plant isn’t cur­rently listed as an inva­sive species on the mas­ter Cal-IPA inven­tory, but appears on a 2007 list of nom­i­nated species. It’s clear from some of the com­ments on a Fresh Dirt post­ing that it’s a grow­ing prob­lem in some areas, my neigh­bor­hood included.

Yes, the stuff is gor­geous. But too high main­te­nance and poten­tially prob­lem­atic in my area. It’s time for us to part ways.

So how will I get my fix for del­i­cate, feath­ery grasses? This year has been my first time grow­ing the native Aris­tida pur­purea, pur­ple three-awn, a species that’s found locally. The plant is shorter than the com­mon feath­er­grass, which might be a bonus, depend­ing on your gar­den sit­u­a­tion. And unlike the nas­sella it has a decid­edly pur­ple color to it while it’s growing–very nice. I’ll post pho­tos once my plants get a lit­tle big­ger. I have no idea if it’ll be the same issue of the plant vol­un­teer­ing all over the gar­den, though I doubt it. Even if it escapes to the wilds, it’ll be in the com­pany of oth­ers of its species. Not a prob­lem.

November 22 2009 | Categories: gardening • my garden | Tags: invasive plants • Mexican feather grass • Mexican feathergrass • Nassella tenuissima • Stipa tenuissima • weeds | 8 Comments »

the chrysanthemum problem

All around town, both road­side and trail­side, the gar­land chrysan­the­mums have been blooming.

The perky spawn of plants that have been grown for cen­turies in China and Japan for their tasty young green leaves, Chrysan­the­mum coro­nar­ium has come to be a big nui­sance in many dis­turbed areas of South­ern California.

But rather than get­ting all neg­a­tive and curs­ing the plant, let me try a dif­fer­ent tack to try to encour­age every­one to rip it out by its pretty lit­tle roots:

Did you know that 100 grams of boiled gar­land chrysan­the­mum pro­vides 51% of your rec­om­mended daily require­ments of vit­a­min A, 40% of vit­a­min C, 21% of iron, and has only 20 calo­ries? (That’s accord­ing to healthalicious.com.)

OregonLive.com offers some kitchen ideas for gar­land chrysan­the­mum: “Lightly saute the leaves and stems or whole 4– to 6-inch seedlings with sesame seeds, gar­lic, gin­ger and soy sauce… Eat raw in salad, add to soups con­tain­ing fresh gin­ger, or dunk in frit­ter bat­ter and deep-fry.”

(Be sure your greens come from a site other than a road­side that might have been sprayed with her­bi­cides by the city. And be sure you’re eat­ing gar­land chrysan­the­mum instead of the some­what sim­i­lar bush sun­flower (encelia) or San Diego sun­flower (viguiera).)

There are of course other rea­sons to pull up this plant. The Tijuana River National Estu­ar­ine Research Reserve site puts it suc­cinctly: “[C]hrysanthemum forms fields that over­take native plants such as Cal­i­for­nia buck­wheat and sagebrush–both these plants pro­vide food and shel­ter for native birds, insects and other animals.”

So in the end gar­land chrysan­the­mum is the per­fect weed. Whether you respond to thoughts of a healthy snack or to appeals of doing what you can to make the world a bet­ter place, you can get out your weed­ing tools and go to town.

A final thought: Wouldn’t it be great for green-conscious restau­rants to offer tasty and hip entrees on their menu that con­tain locally-harvested gar­land chrysan­the­mum greens that oth­er­wise would have been dam­ag­ing the ecosys­tem? Or maybe we could stock stalls at farmer’s mar­kets with piles of the stuff? Why not turn this over-abundant inva­sive plant into a resource that could be cropped, improv­ing the local land­scape at the same time?

Eat up, everyone!

This post is ded­i­cated to Out­of­doors, who first thought up the idea of ded­i­cat­ing the 13th of the month to posts on inva­sive species.

May 13 2009 | Categories: landscape • plant profiles | Tags: Chrysanthemum coronarium • garland chrysanthemum • invasive plants • weeds | 6 Comments »

…and some not so garden-worthy

You could prob­a­bly gather together six gar­den­ers and get six dif­fer­ent opin­ions of what would make a plant garden-worthy. But I sus­pect there might be some­what more agree­ment on cer­tain other plants that prob­a­bly shouldn’t be included in a gar­den. Here are some encoun­ters from Sunday’s trip to Tecolote Canyon that would fall eas­ily into most people’s less-than-desirable category.

I’ll have to admit to actu­ally lik­ing this plant to the right. Dur­ing the win­ter it drops its leaves and is an attrac­tive thicket of upright or sprawl­ing branches. This time of year it starts new growth that has this warm red-brown col­oration. It’ll flower soon, and then set some loose clus­ters of white berries. Pretty, yes, and native, and impor­tant to wildlife. But this is poi­son oak. Maybe not the best choice for small back­yard gardens…

Most of the rest of my list below is com­prised of exotic plants that have staked a claim for them­selves at the expense of the native species. Dif­fer­ent loca­tions have their own list of inva­sives, so what you see below is tai­lored to South­ern Cal­i­for­nia. Some of these plants could be good choices for other loca­tions. Oth­ers would be trou­ble almost any­where you grow them.

[ At this point I’d like to ded­i­cate the rest of this Fri­day the thir­teenth post to Out­of­doors, who last month devoted her Fri­day the thir­teenth post to inva­sive plant species. ]

I won’t go into too much detail about this trou­ble­some trio. Peo­ple have been work­ing hard to get the word out on pam­pas grass, green foun­tain grass, and ice­plant. The grasses, in par­tic­u­lar, can be gor­geous things in gar­dens, wav­ing in the breeze and lend­ing their dra­matic form to groups of softly mound­ing land­scape shrubs. You can see why peo­ple want to grow them. But are they garden-worthy in South­ern California?

All three of these quickly check out of people’s gar­dens and make for the wilds. I found both grasses and plenty of ice­plant escaped into the canyon, here on this hill­side and in other spots. So, as pretty as they can be–and I con­sider this drift of foun­tain grass in the sec­ond photo to be par­tic­u­larly poetic–these three would be bet­ter left in their native lands, or grown in cli­mates where the weather might limit their spread.

This is the first flower I saw this sea­son on the local plants of onion weed (Aspho­delus fis­tu­lo­sus). The first time I saw it I thought it was a wild­flower and wanted some for my gar­den. In full bloom the stalks of white flow­ers are an impres­sive sight. But they do spread like crazy. Not a good choice for the garden.

This com­bi­na­tion of plants looks as impres­sive as any plant­ing assem­bled by prac­ti­tion­ers of the New Peren­ni­als gar­den move­ment. But once again, the plants aren’t really wel­come addi­tions to the canyon. In the fore­ground is teasel (Dip­sacus sp.), a plant with excel­lent year-round archi­tec­tural struc­ture but hav­ing inva­sive ten­den­cies that are con­sid­ered “Mod­er­ate” by the Cal­i­for­nia Inva­sive Plant Coun­cil (Cal-IPC). Here it’s set against a back­ground of last season’s black mus­tard, a prob­lem in these parts since it was intro­duced by the Span­ish in the eigh­teenth cen­tury. The Cal-IPC only con­sid­ers the mustard’s rangi­ness to be of “Mod­er­ate” con­cern, but also states: “Pri­mar­ily a weed of dis­turbed sites, but can be locally a more sig­nif­i­cant prob­lem in wild­lands.” I’d say it’s a more sig­nif­i­cant pest locally.

Fen­nel can be attrac­tive in the herb gar­den, but like the rest of the inva­sives in this post, this is another plant that gets around. Its over­all unde­sir­able impacts are con­sid­ered “High” by the Cal-IPC. If I see fen­nel offered in the local nurs­eries it’s usu­ally the bronze col­ored strain. It’s less vig­or­ous, but all forms are con­sid­ered inva­sive. I do wish this were a bet­ter choice for gar­dens because it hosts swal­low­tail but­ter­flies, but at least there’s plenty of swal­low­tail food out in the local canyons. The but­ter­flies won’t starve. Okay, I’ll pass.

Say “Old Cal­i­for­nia” to any­one who’s lived in these parts for long, and this plant will prob­a­bly come to mind. The Brazil­ian Peru­vian pep­per tree forms a gor­geous tree with long, del­i­cate leaves that move any time there’s a breeze. But unfor­tu­nately the plants develop berries that the birds find irre­sistible. While the Cal-IPC con­sid­ers their threat to Cal­i­for­nia to be only “Lim­ited,” there are plants that would be bet­ter choices.

The Aus­tralian pep­per­mint wil­low (Ago­nis flex­u­osa), although not a native plant, is a good drought-tolerant sub­sti­tute that looks a bit like the pep­per tree but doesn’t share its inva­sive ten­den­cies. If you must have a del­i­cate weep­ing tree that says “Old Cal­i­for­nia” but don’t mind a lilt­ing Aus­tralian accent, this would be a bet­ter choice–and you can get vari­eties with either green or dra­matic black foliage. Or you could give up alto­gether on the colo­nial look and go in for any of the truly native trees. It doesn’t get any more “old Cal­i­for­nia” than that.

As I reread this post I’m struck that I’m prob­a­bly not doing a par­tic­u­larly good job of dis­cour­ag­ing peo­ple from grow­ing these plants. I keep going back to the beau­ti­ful redeem­ing qual­i­ties of these inva­sives, and I guess that’s why they con­tinue to be such a prob­lem. The mind tells you they might be bad news, but some­times it’s hard to say no.

With this last image I leave the plant king­dom and turn to another species that’s native to the local canyons. This one I think you’ll def­i­nitely agree you wouldn’t want around. I won’t assume that you like snakes any more than I do, so if you want to see the pic­ture you’ll have to click HERE.

Still, who among you doesn’t think baby ani­mals are just the cutest things? Now, every­body, say “awwwww”… This is a lit­tle baby south­ern Pacific rat­tler, prob­a­bly no longer than my fore­arm and too young to rat­tle. I’m deathly afraid of snakes but man­aged to fend off the fear to snap the pic­ture and watch the snake as it coiled itself defen­sively and make like a sidewinder, slid­ing back­wards into the grasses.

I have to respect these ani­mals since they do won­ders to keep down the rodent pop­u­la­tion. And they’re every bit as native as the poi­son oak I showed ear­lier. But after hav­ing had one of these in the back­yard fac­ing off against my cat, I’ve def­i­nitely decided this is another species that’s not garden-worthy, at least in my enclosed lit­tle space.

I admit it, I’m a wimp. Nature isn’t always con­ve­nient is it? But throw out the rat­tlesnakes and pam­pas grass and black mus­tard and fen­nels and you’re still left tens of thou­sands of cool and friendly selec­tions to invite into the garden.

March 13 2009 | Categories: gardening • landscape • landscape design • places • plant profiles | Tags: Agonis flexuosa • Asphodelus fistulosus • black mustard • Brassica nigra • Dipsacus fullonum • fennel • invasive plants • onion weed • pampas grass • pepper trees • peppermint willow • snakes • teasel | 4 Comments »

that’s sooooo 1970s

A house down the street has had a contractor’s truck parked out­side of it for a while now. The owner said she’s remod­el­ing the kitchen and bath. Not any time too soon, accord­ing to John, who dur­ing our last time in the house noticed that those rooms oozed the stuff that 1975 was made of: fab­u­lous 70s mod­ern appli­ances, wood­grained formica, beige tile floors. There’s noth­ing wrong with any of these mate­ri­als, but the rooms looked like they were sealed in a time cap­sule, an easy thing to hap­pen to rooms that are so expen­sive to remodel.

Some gar­dens around town seem to have the same aura about them. You sense that the gar­den was planted all at once–probably by a pickup truck landscaper–from what was avail­able and fash­ion­able and con­sid­ered reli­able at the time. Decades later the plant­i­ngs will look untouched–the same plants in the same places (often planted too close together or too near a house). Things might be pruned a lit­tle, or there might be a mature row of some­thing with a miss­ing plant. But oth­er­wise untouched.

I tend to think of gar­dens as evo­lu­tion­ary projects, espe­cially when they’re in the hands of curi­ous gar­den­ers. It’s always a bit of a shock to see one of these botan­i­cal time cap­sules. Com­mer­cial plant­i­ngs seem to be the worst offend­ers. Here, to the right, is a lovely pair­ing of melaleu­cas with ice­plant at the local EZ-Lube that seems pick­led in about 1983.

So which plants shout that they’re from a cer­tain decade? I tried to sort that out based on what you see in South­ern Cal­i­for­nia. (Other cli­mates will have their own char­ac­ter­is­tic plants.)

This is just a quick and impres­sion­is­tic draft that’s based on when plants were cheaply avail­able and most pop­u­lar, not nec­es­sar­ily when they were intro­duced. Many of them are still com­monly avail­able today and are hardy, worth­while choices for the gar­den. Oth­ers have turned out to be inva­sive dis­as­ters that have prompted nurs­eries to stop car­ry­ing them.

I’m sure I’ve mis­placed a few plants by a decade or two. You must have addi­tions of your own!

1960s

• Hol­ly­wood Twisted Juniper (Junipe­rus chi­nen­sis ‘Toru­losa’). “Hol­ly­wood” and “twisted” some­how seen to go together nicely… My mother cov­eted them, and I still think they’re pretty wild and crazy plants. Of course in the 1960s and 1970s, the junipers were a lot smaller than this.
• Ital­ian Cypress (Cupres­sus sem­per­virens). The house my par­ents pur­chased in 1968 had two lit­tle plants of these flank­ing a win­dow. When we moved out of that house they weren’t so little…
• Arborvi­tae (Thuja sp.)
• Japan­ese Pit­tospo­rum, Japan­ese Mock Orange (Pit­tospo­rum tobira)
• Japan­ese Gray-bark Elm, Japan­ese Zelkova (Zelkova ser­rata). These go back years, but there were lots of street plant­i­ngs in 1950s and 1960s suburbs.

And speak­ing of zelko­vas, my neigh­bor­hood had hun­dreds of them as street plant­i­ngs. Even­tu­ally they began lift­ing the side­walks, and then grew up into the power lines. One by one the own­ers took out the trees. Then, the city took out the power lines and put them under­ground, about the same time they repaired the side­walks. We have a few of the trees left.

1970s

• Ole­an­der (Ner­ium ole­an­der), shown here in a free­way plant­ing down the hill from me. They’re hardly ever planted any­more. Although drought-tolerant, they can get bad scale infes­ta­tions. The nail in the cof­fin for this plant, though, was the fact that they’re poi­so­nous if ingested or burned.
• Natal Plum (Carissa macro­carpa)
• Ice­plant (var­i­ous species), some are con­sid­ered inva­sive in South­ern California
• Var­ie­gated Japan­ese Euony­mus (Euony­mus japon­i­cus ‘Aureo-marginatus’)
• Melaleuca, Paper­bark Tree (Melaleuca quin­quen­ervia), now on the fed­eral inva­sive plant list and the scourge of many states

Here’s a tran­si­tional 1960s-1970s plant­ing at the bank down the street. More twisted junipers, paired here with natal plum.

1980s

• Foun­tain Grass, Green Foun­tain Grass (Pen­nise­tum setaceum), the Cal­i­for­nia Inva­sive Plants Coun­cil lists these as “Invasive–Do Not Plant–Invasive” (hmmm, they might be inva­sive…) on their web­site.

  Photo by Car­olyn Mar­tus from the Cal-IPC site [ source ]

• Red Foun­tain Grass, Pur­ple Foun­tain Grass (Pen­nise­tum setaceum ‘Rubrum’)–I still have three in the front yard and love them. Unlike the above, they’re ster­ile and don’t sow them­selves every­where. [ Edit June 11, 2010: The red foun­tain grasses are def­i­nitely not ster­ile, though they still are far less inva­sive than the green ver­sions of the species. It’s best not to plant these any­where where thye might escape. ]
• Aga­pan­thus
• Euge­nia, Aus­tralian Brush Cherry (Syzy­gium pan­ic­u­la­tum). These make tidy, fine-leaved clipped hedges. But when the euge­nia psyl­lid hit in 1988 plant­i­ngs every­where started to look awful. They dis­ap­peared from the trade.
• Indian Hawthorn (Rhaphi­olepis indica)
• New Zealand Flax (Phormium sp. and hybrids)

1990s

• Mex­i­can Feather Grass (Stipa or Nas­sella tenuis­sima), now quickly mov­ing onto many people’s lists of obnox­ious if not inva­sive plants. I started with two and now have half a dozen. I’d have thou­sands if I didn’t pull out a cou­ple dozen seedlings every week! This is the park­ing strip of a neigh­bor a few blocks away who prob­a­bly put in one or two plants herself.
• Laven­ders (Laven­dula sp.)–I still have one of these.
• Blue Fes­cue (Fes­tuca ovina glauca)–and sev­eral of these…
• Kan­ga­roo Paw (Anigozan­thus sp.)

2000s

• ???????

  What plants will the future decide define the Bush decade? What sturdy plants are the nurs­eries offer­ing that will run their course as peo­ple get tired of them or the plant’s inva­sive poten­tial are revealed? For one, I’m see­ing a lot of Cordy­line aus­tralis. I like these a lot, but they sud­denly seem to be planted every­where, many in loca­tions where they look good as two-foot ado­les­cents but will quickly out­grow their spots. And there are cheap queen palms (Sya­grus roman­zof­fi­ana) going into the ground everywhere.

  I’m sure there are dozens more.

February 19 2009 | Categories: gardening • landscape design | Tags: heirloom plants • invasive plants • popular plants | 15 Comments »

green immigrants

Here are a few more selec­tions that you might find inter­est­ing from Amer­i­can Per­cep­tions of Immi­grant and Inva­sive Species: Strangers on the Land, by Peter Coates, pub­lished in 2006.

Before Colum­bus brought seeds and cut­tings along on his sec­ond voy­age to the West Indies, North Amer­ica was home to less than 1 per­cent of the world’s total com­ple­ment of cere­als, starches, fruits, and vegetables.

Today, the only crops of sig­nif­i­cant com­mer­cial value native to the ter­ri­tory that became the United States are cran­berry, blue­berry, pecan nut, sugar maple, sun­flower, and tobacco–a fact that offers elo­quent tes­ti­mony to the great ser­vice that has been duly ren­dered by a sting of public-spirited Americans…

No Amer­i­can pub­lic ser­vant since [Thomas] Jef­fer­son deserves more credit for trans­form­ing the for­eign into the com­mon than David G. Fairchild. In his capac­ity as agri­cul­tural explorer in charge at the Sec­tion for For­eign Seed and Plant Intro­duc­tion from 1898 until 1928, Fairchild brought the navel orange to Florida and Cal­i­for­nia from Brazil and over­saw the intro­duc­tion of Italy’s seed­less grape and China’s dry land pis­ta­chio. His most notable con­tri­bu­tions, how­ever, were in the intro­duc­tion of the Chi­nese soy­bean and…the tree that became an essen­tial prop of Wash­ing­ton, D.C.‘s mon­u­men­tal land­scape, adorn­ing the Tidal Basin: the Japan­ese flow­er­ing cherry tree.

Fairchild’s encoun­ters with the infa­mous vine that “ate the South”…left him some­what chas­tened. He first came across kudzu about 1900 while tour­ing Japan, where this wild, semi­woody peren­nial was fed to live­stock. In his auto­bi­og­ra­phy he recalled a visit to a “kudzu enthu­si­ast” in Chip­ley, Florida, who was renowned for singing its praises as a for­age crop in the early 1900s, despite his neigh­bors’ dis­trust. “When­ever I think of that night’s talk with the kudzu pio­neer,” recalled Fairchild, “I have a spe­cial feel­ing of pride in what might be called our Amer­i­can will­ing­ness to try some­thing new, whether it be a new for­age crop, a new food, or any one of a thou­sand new, machine-made gad­gets.” Fairchild, who con­fessed that “per­haps I have an undue pas­sion for the new,” retained his faith in kudzu for quite some time, despite its pro­cliv­ity to spread at will. By the late 1930s, how­ever he was express­ing his grow­ing reser­va­tions in print. The seeds he brought back from Japan and planted on his prop­erty in Florida “‘took’ with a vengeance, smoth­er­ing every­thing they got onto, and pretty soon we became alarmed. Feel­ing that the kudzu was too much for us, we began to cut it out.”

Fairchild finally returned home, so to speak, in 1946, when invited to make his selec­tion for the “My Favorite Tree” guest col­umn in the jour­nal of the Amer­i­can Forestry Asso­ci­a­tion (the nation’s old­est con­ser­va­tion orga­ni­za­tion, founded in 1875). After men­tion­ing a string of exotic also-rans, but dis­card­ing them as unsat­is­fac­tory, he recalled that he had seen his first grove of Cal­i­for­nia coastal red­woods (Sequoia sem­per­virens) fairly late in life, at a time when he was still besot­ted with exotic Asi­atic promise: “A feel­ing of utter paral­y­sis over­took me and the pas­sion for plant­ing trees, my puny lit­tle trees, any­where, became distasteful.”

The sto­ries in the book are great, and the social com­men­tary is com­pelling. Unfor­tu­nately, every now and then a botan­i­cal clinker drops into the book’s pages, such as the one that fol­lows the quote on red­woods imme­di­ately above, where the author waxes, “Though the red­wood is only really found in Cal­i­for­nia (there is a tiny patch in the most south­west­erly cor­ner of Ore­gon), it is arguably more Amer­i­can than any other tree in the United States inso­far as it has no rel­a­tives, near or dis­tant, in any other coun­try.” Like, um, what about the Chi­nese dawn red­wood (Metase­quoia glyp­tostroboides)?

Okay, this isn’t a book you read for the botany, but it’s a wor­thy and thought­ful work on plants and the human con­di­tion, per­fect for late win­ter read­ing as you con­tem­plate the impend­ing bloom­ing of your cherry trees.

Although it’s pri­mar­ily about bio­log­i­cal immi­grants to North Amer­ica, Peter Coates points occa­sion­ally out that the immigrant-carrying boats sailed both directions:

The native oaks of Britain and the United States were greatly admired by J.C. Loudon, a lead­ing British hor­ti­cul­tur­ist of the mid-nineteenth cen­tury. He pro­nounced them “the most beau­ti­ful of trees.” Yet exotic trees had already become a manda­tory ingre­di­ent of the “polite” British land­scape enclosed within pri­vate estates. Loudon him­self was one of the trend­set­ters who insisted that, notwith­stand­ing the oak’s charms, “no res­i­dence in the mod­ern style can have a claim to be con­sid­ered as laid out in good taste, in which all the trees and shrubs employed are not either for­eign ones, or improved vari­eties of indige­nous ones.

The most sought-after of these arbo­real exotics were hardy North Amer­i­cans. Britons were ruth­lessly con­de­scend­ing toward Amer­i­can artis­tic achieve­ments at this time. “In the four quar­ters of the globe,” Syd­ney Smith famously inquired [in 1820], “who reads an Amer­i­can book?” or goes to an Amer­i­can play” or looks at an Amer­i­can pic­ture or statue?” Yet no one asked “who plants an Amer­i­can tree?”

February 10 2009 | Categories: gardening • landscape • landscape design • quotes | Tags: Add new tag • agriculture • books • David G. Fairchild • exotics • invasive plants • kudzu • native plants • Peter Coates • trees | 3 Comments »

the long brown season

When you spend your time in San Diego’s well-watered burbs it’s easy to for­get that you’re liv­ing in the mid­dle of a desert. The last sig­nif­i­cant rain­fall in town occurred in Feb­ru­ary, and the unir­ri­gated nat­ural lands around town have long ago begun their trans­for­ma­tion into the long brown season.

My recent lit­tle excur­sion to Los Peñas­qui­tos Canyon, a local open-space pre­serve between San Diego and Del Mar, gave me a chance to see what the nat­ural world is doing in these parts.

Not every­thing is brown, of course. Some plants are tapped into loca­tions with resid­ual mois­ture. Oth­ers have adapted to the cli­mate and have the sta­mina to stay green year-round.

Here are a few of the plants still show­ing col­ors other than brown:

Flat-topped buck­wheat (Eri­o­gonum fas­ci­c­u­la­tum) a native plant.

Wild rose (Rosa cal­i­for­nica) a native.

Fen­nel (Foenicu­lum vul­gare) an exotic, inva­sive species. This is the culi­nary plant from the Mediter­ranean that has escaped into the wilds.

Poi­son oak (Tox­i­co­den­dron diver­silobum) a native–one of the few plants that turns blaz­ing red in the fall. Even now, it’s show­ing some of that red color.

This­tle in bloom. I’m not sure if this is native or not, but it’s not the hyper-nasty Russ­ian this­tle (the dried flow­ers of which are shown in the large photo above). [Correction/edit August 1: This is actu­ally a teasel, not a this­tle. Like the escaped fen­nel above, this too is a rene­gade exotic species. Pretty, though…]

It’s a con­di­tion of our con­sumer cul­ture and times to want what we don’t have. Liv­ing in San Diego, most of the plant mate­ri­als that peo­ple expect to find in their home gar­dens fall out­side of the cat­e­gory of what occurs nat­u­rally or is well-suited to the area.

It’s always instruc­tive to visit the nat­ural pre­serves to see plants–even the nasty invasives–that are supremely well-designed to live in this cli­mate. Some of the plants in these parks would do extremely well in gar­dens. But it’s hard let­ting go of plants that many of us asso­ciate with places we’ve lived in and even peo­ple we’ve known.

My own yard has sev­eral areas that I con­sider my guilty plea­sure zones. I have pieces of a bromeliad and a kahili gin­ger that I was given in the 1970s, as well as the green rose from that I dug up from the house where I grew up in the Los Ange­les area. And I’m a nat­ural born col­lec­tor who has a hard time say­ing no to inter­est­ing plants. These plants all require some water and tend­ing beyond what nature brings.

But they’re coun­ter­bal­anced by gar­den areas planted with drought-tolerant species, local and intro­duced, that receive almost no water and atten­tion over the sum­mer. As time goes on, I’ll be expand­ing those areas. Don’t expect me any time soon, how­ever, to plant poi­son oak, as pretty and hardy as the plant is. I have my lim­its as to how much true nature I want in my garden…

July 29 2008 | Categories: gardening • places | Tags: drought-tolerant landscaping • invasive plants • Los Penasquitos Canyon Preserve • native plants • seasons • summer | 4 Comments »