[ Lost in the Landscape ]

after the rain delay

The rain last week­end cleared out long enough for us to install the shade panel we’d constructed.

The fence you see faces north by north­west. Any­thing grow­ing in the bed is in total shade for sev­eral months. About this time of year, though, the sun swings north, and things start to get sun expo­sure in the later parts of the day. We removed the termite-munched patio cover that shaded the del­i­cate plants last fall–it had to go–but sud­denly time was of the essence in restor­ing shade.

This is where a few shade denizens live in the bed…

…along with John’s col­lec­tion of orchid cac­tus, Epi­phyl­lum, that he’s amassed over the years. We also have a small assort­ment of hang­ing tilland­sias and some trop­i­cals, includ­ing a few sur­viv­ing orchids from my rabid orchid-growing days two decades ago.

This week­end has turned rainy again, fill­ing many of the holes in the shade screen with water. It’s slowed down mov­ing the plants to their new home, but I won’t com­plain about the water we’re getting.

We’re already two inches ahead of the entire rain­fall for last sea­son (July 1, 2008 to June 30, 2009). And last month’s rain accu­mu­la­tion alone, 5.4 inches, came close to the 5.5 total for all of 2009. Still we have a cou­ple inches to go before we can even claim an aver­age rain­fall year.

This season’s rain is fill­ing up ver­nal pools after sev­eral years of dis­ap­point­ments. Fri­day I stopped by some pools with a biol­o­gist to scope out a poten­tial field trip for the local native plant soci­ety. Ver­nal pools are among the most threat­ened habi­tats locally. The occur on our mesa tops, areas that prove irre­sistible to devel­op­ers because they’re flat and require less soil prepa­ra­tion than canyon bot­toms or slopes.

Young plants were every­where, includ­ing those of San Diego mesa mint (Pogog­yne abram­sii), a plant on sev­eral endan­gered species lists. If the rains keep up, it looks like it’s going to be a great year for them.

February 28 2010 | Categories: gardening • landscape • my garden | Tags: endangered species • hardscape • San Diego mesa mint • shade • vernal pools | 4 Comments »

rain delay

It’s almost never too rainy to gar­den, and of course it’s never too wet to blog. But some out­door projects have had to be put on hold temporarily.

Yes­ter­day, when it was still dry, we started to con­struct a shade panel to begin to replace a patio cover we tore down last fall. Many of the plants on the patio are shade plants, and we still have some shade plants hang­ing in the shade of the green­house. As the weather warms and the sun begins to burn hot­ter in the sky many of the plants are start­ing to need some cover.

We got this far on the panel project yes­ter­day. It’s a ten-by-four foot frame of alu­minum, with an inset of per­fo­rated alu­minum mesh. The diag­o­nal cross pieces are for both struc­tural sup­port and what I hope will be a level of coolness.

And then it began to rain: Light mist now and then yes­ter­day, and occa­sional rain­squalls this morn­ing. Not safe weather for oper­at­ing elec­tric devices out­side, but noth­ing to stop me from pulling some weeds and then stop­ping by my favorite local nurs­ery, Wal­ter Ander­sen Nurs­ery. There was a bald spot out front and I needed a plant to fill it. One plant.

But the nurs­ery was ooz­ing green life force that proved irre­sistible and I came home with three instead: white flow­er­ing cur­rant (Ribes indeco­rum), Route 66 Cal­i­for­nia fuch­sia (Zauschne­ria cal­i­for­nia ‘Route 66′) a sec­ond plant of Cean­othus ‘Tuxedo’ to go with one I pur­chased last year. I’ve resolved to plant at least fifty per-cent Cal­i­for­nia native plants, and I think I suc­ceeded. The first two qual­ify, and the last gets par­tial credit. (I have a post in the works describ­ing why.)

Of course for me rainy days turn into oppor­tu­ni­ties to col­lect more rain­wa­ter for the prima donna bog plants that detest the water that comes from the tap. At this point I prob­a­bly have sev­eral months’ sup­ply in buck­ets and bar­rels. And the ground will hold its mois­ture and require min­i­mal water­ing for sev­eral weeks. I wouldn’t want to force our county’s golf courses go with­out water, would I? (Well, yes, actu­ally, I would. Yet another blog post…)

February 20 2010 | Categories: gardening • my garden | Tags: collecting rainwater • rain • shade | 8 Comments »

from leaf to mulch

For my first attempt at par­tic­i­pat­ing in Pam at Digging’s Foliage Follow-up Day I looked under the grape­fruit tree for inspi­ra­tion. As the leaves fall from the tree they go from green to brown to gray before they finally become part of the com­post that enriches the top of the soil. That last stage pro­duces some gor­geous arti­facts, where what’s left is mostly the thicker veins of the leaf. Even as the leaf tis­sue between the veins becomes com­post or is con­sumed by the lit­tle crit­ters liv­ing in the mulch, the struc­ture of the leaf still remains.

Here’s a series of pho­tos of those last rec­og­niz­able traces of formerly-living leaves. Most of the below take advan­tage of the fact that the shadow can seem much more sub­stan­tial as the thing itself. Maybe it’s a metaphor for the last­ing power of a leaf that is about to become com­post? Some­thing about the cycle of life?

February 16 2010 | Categories: gardening • my garden | Tags: compost • grapefruit • leaves • mulch | 18 Comments »

plants as compass (february bloom day)

I was look­ing at my bloom­ing Agave atten­u­ata and noticed some­thing for the first time. The flow­ers on its spike have been open­ing asym­met­ri­cally, with the south-facing buds open­ing a few days ear­lier than the ones on the shaded side. I guess it’s the agave equiv­a­lent of moss grow­ing on the shaded north side of a tree trunk. As I looked at all the agaves in the neigh­bor­hood, I was notic­ing the same thing: All the south-facing buds open first. It makes sense, I guess, with the sun-warmed buds devel­op­ing sooner than the ones grow­ing in the shade. There must be a botan­i­cal term for this–I’ll see if I can’t look it up sometime.

Some­thing else I noticed the other week was that two of the lit­tle rosettes grow­ing under­neath the growth pro­duc­ing the big spike are also bloom­ing. They’re nice, but the blooms get pretty lost in the foliage.

And com­pared to the big main spike, which must be some­thing like twelve or more feet from base to tip, you can see how it’d be easy to over­look the lit­tle pups…

In the photo above you can make out this big red aloe in the back­ground, Aloe arborescens. The clump began as a one-gallon plant in the early nineties. Now it’s prob­a­bly six feet tall and twelve across.

Feb­ru­ary in South­ern Cal­i­for­nia is a busy month for flow­er­ing plants. Here’s a selec­tion of what else is bloom­ing in the garden.

This raised planter of Oxalis pur­purea is the first part of the gar­den that vis­i­tors encounter as they head up the front steps. Dozens of white flow­ers and a lone pink one in the front. Oops.

Ver­bena lilacina, greened up from the rains, begin­ning to hit its stride.

One of sev­eral plants of Nuttall’s milkvetch, Astra­galus nut­tal­lii, that I raised from seed last summer.

Snapdragon-relative Galvezia spe­ciosa ‘Fire­cracker,’ never a pro­lific bloomer for me, though mine’s a young plant.

The pink-flowered, purple-leaved form of Oxalis pur­purea.

Car­pen­te­ria cal­i­for­nica, a Cal­i­for­nia plant that reminds me a lot of sasan­qua camel­lias in its sim­ple con­trast of sta­mens against broad petals.

First flow­ers on Phlomis mono­cephala.

Feb­ru­ary flow­ers on a yel­low cras­sula that I’ve for­got­ten the name of…

The final blooms of the sea­son on another cras­sula, your basic jade plant, Cras­sula ovata…

The fra­grant Solanum parishii, a wide­spread Cal­i­for­nia native, doing bat­tle on the slope gar­den against ice­plant, Alger­ian ivy and Bermuda buttercup.

Free­way daisies (Osteosper­mun) below, with black sage (Salvia mel­lif­era, pros­trate form) above.

Keep­ing up the daisy theme, Arc­to­tis acaulis hybrid…

Another acto­tis, ‘Big Magneta’…

…and a final photo, a final arc­to­tis, shown against a piece of gar­den art made from glass, steel, and concrete.

As always, my thanks to Carol at May Dreams Gar­dens for host­ing Gar­den Blog­gers’ Bloom Day. Even with snow on the ground many places up north, there’s still plenty in bloom today in warmer, more south­ern loca­tions, and on win­dowsills and green­houses around the world. Check them out [ here ].

February 14 2010 | Categories: gardening • my garden | Tags: Agave attenuata • flowers • Garden Bloggers Bloom Day • gbbd • native plants | 32 Comments »

plants falling asleep

White Oxalis pur­purea clos­ing up for the evening.

Detail of white Oxalis pur­purea think­ing about some shut-eye.

Purple-leaved Oxalis pur­purea clos­ing up in the late after­noon shade.

A lot of the flow­er­ing plants in the gar­den don’t bother open­ing their petals until the sun’s up and then shut their flow­ers as soon as the light begins to fade and tem­per­a­tures drop in the after­noon. Over the week­end I was notic­ing this going on with my oxalis plants and, less dra­mat­i­cally, with my arctotis.

There must be a name for this behav­ior, I thought, and so off I went look­ing for an answer. Before long up pop three inter­est­ing words: pho­tonasty, ther­monasty and nycti­nasty.

Accord­ing to one of the sources, the Text­book of Botany by Chhat­wal and Singh, pho­tonasty hap­pens when a plant senses light and reacts to it by open­ing or clos­ing its flow­ers. Because of this, morn­ing glo­ries open in the…well, morn­ing. Then there’s ther­monasty, where flow­ers react pri­mar­ily to tem­per­a­ture. Tulips will open with a rise of 2–3 degrees Cel­sius, while a cro­cus will zip open when the tem­per­a­ture rises just a half degree.

And then there’s the more com­plex phe­nom­e­non of nycti­nasty, which “is influ­enced by the inten­sity of light and also tem­per­a­ture dif­fer­en­tials, the for­mer stim­u­lus being more pow­er­ful and effec­tive. The foliage leaves and also the flo­ral leaves in many species of plants…attain dif­fer­ent posi­tions at day time and at night viz dur­ing the day, the leaflets remain open or spread up in case of Oxalis, clever beans, alfalfa, etc., while by the onset of dark­ness they close down. This is also known as sleep movement.”

Yes­ter­day after­noon was pretty bright, but cool. The oxalis barely opened before shut­ting back up. So it requires both heat and warmth to open fully. So nycti­nasty makes sense. The arc­to­tis seemed to open more fully, ear­lier in the day. My guess is that they respond more sim­ply, mainly to light, which would mean that they exhibit pho­tonasty. (What’s truly going on could be lots more com­plex than this and really might only be solved by exper­i­men­ta­tion, a point made in an arti­cle, “Flower open­ing and clo­sure: a review” by Wouter G. van Doorn and Uulke van Meeteren in the Jour­nal of Exper­i­men­tal Botany. Read the inter­est­ing text [ here ].)

Next I need to find out what “clever beans” are.

In my web trawl it turns out I’m not the only gar­den blog­ger look­ing at this phe­nom­e­non this week. Tilthy Rich took a quick spin around nycti­nasty [ here ]. Maybe he has the same plants bloom­ing, mak­ing him ask the same questions…

Flow­ers of Arc­to­tis acaulis ‘Big Magenta’ begin­ning to fold up for the night.

Another clone of Arto­tis acaulis clos­ing up in the after­noon: Pho­tonasty? Ther­monasty? Nyctinasty?

February 08 2010 | Categories: gardening • my garden | Tags: arctotis • flowers • nyctinasty • oxalis • photonasty • thermonasty | 13 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 »