Who's Blooming Today: Cistus purpureus

Today the purple (or orchid) rockrose, Cistus purpureus, began its show. This is one of my favorite shrubs: drought tolerant, evergreen, resinously aromatic foliage, and of course these flowers that go with any color I can imagine. I especially enjoy it with silver companions such as Salvia chamedryoides, Santolina, and Lavandula stoechas.



In fact, my only problem with the Cistus is that it gets big - up to 4' wide if left unchecked. I'll be heading mine back after its first bloom cycle, but we all know it's a futile effort. I've got 3 of these fellows in my Palo Alto garden, all runts adopted from the nursery's clearance shelf at the end of last summer. I must have been very good in a past life for such good garden karma now!

Massive Water Discovery Ends California Drought

SACRAMENTO, Calif. - April 1, 2009 - Governor Arnold Schwarzenegger and the California Department of Water Resources (DWR) today lifted the state's year-long drought emergency order on the news that an enormous water reservoir has been discovered along California's western border.

Although the exact size of the aquifer has yet to be determined, reports indicate it may be hundreds of miles across and more than 10,000 feet deep, billions of gallons in total. "We are delighted to say, the drought is over," Schwarzenegger proclaimed at a beachfront press conference, a gleaming drinking glass on his podium. "This discovery will provide enough water for every man, woman, child, farmer, rancher, business, school and park in our great state to live the California lifestyle without ever again worrying whether there is enough water to waste."

California's $36 billion agriculture industry applauded the announcement. "Our crops, orchards and ranches have been in decline for well over a decade now," said Andrew Simon of the California Department of Food and Agriculture (CDFA). "This [discovery] means we will be able to get back to our business of feeding the world."

Indeed, the state's farmers may be able to not only regain lost ground, but even expand into new markets: low lending rates, coupled with property foreclosures throughout the state, are fueling a new era of agricultural expansion as farmers buy entire subdivisions and convert them to arable land. "We're processing a record number of loan applications," said banker Toiya Dobrov, whose clientele includes family farms throughout the Central Valley. "Water is going to be the new gold."

The newly discovered reservoirGov. Schwarzenegger said the state will petition the federal government for funds from the recently approved stimulus package to develop filtration, conveyance and distribution systems throughout the state, a further boon to California's languishing economy. "This is the genius of President Obama's economic recovery plan," he said. "Investing in our infrastructure will produce exponential returns when we give people jobs and deliver water to where they work and where they live." The state already is in discussion with neighboring Nevada and Arizona to export its newfound bounty to those parched regions, and plans are under study for a "main vein" pipeline to route water from California east through the entire country. "This could be the next transcontinental railroad," said Schwarzenegger, announcing that project bids will be solicited within weeks.

The California Landscape Contractors Association (CLCA) and state chapters of the Association of Professional Landscape Designers (APLD) and American Society of Landscape Architects (ASLA) also welcomed the news. In a joint statement, the groups say they "look forward to creating landscapes that can gulp rather than sip, that evoke Shangri-La rather than the Sahara. For too long we and our clientele have endured the constraints of a Mediterranean climate; now, with our abundance of sunshine matched only by our access to water, we can live in any garden we desire." No comment was available from the Synthetic Turf Council, one of the few industries analysts expect will not profit from the discovery.

Ironically, the aquifer was discovered by two recently unemployed construction workers, Eric Lucas and Dante Christopher, both of Palo Alto, Calif. Although neither has a background in hydrology or environmental science, both knew immediately they were on to something big last month while visiting the nearby coastal town of Pescadero. "We were just chilling on the beach," said Mr. Lucas. "The next thing I know, Dante is shouting 'Water! Water!' First I called 911," he said, "but we got disconnected, so I called the newspaper" who in turn called the state water agency. Neither man is aware of any plans to name the body of water in their honor.

The sheer size of the reservoir has made mapping of its boundaries tedious, which in turn has inflamed long-simmmering tensions between California and its neighbors. The states of Oregon, to the north, and Hawai'i, to the east, both claim the water reaches into their territories. And in what could turn a domestic dispute into an international incident, Mexico also contends that a portion of the water is theirs, a claim Gov. Schwarzenegger downplayed. "The proud nation of Mexico and the great state of California have a long and rich history of sharing resources," he said, "and we certainly will work together to ensure an equitable distribution of this resource as well."

The discovery has raised almost as many questions as hopes. One story circulating the Internet claims the volume of water actually could increase over time due to factors related to global warming, to which a DWR spokesman responded "we can only hope." Other critics have noted the water's purity is unproven, and it may be polluted by vegetation and animal waste.

The DWR spokesman refused comment on another allegation, that extreme salinity in the water makes it unfit for drinking or irrigation. "This is a proud day for our state and our nation" said the spokesman. "Let's not let irresponsible rumor-mongering dry up our celebration."

Q&A: Planter Boxes on Concrete

Raymond in Sonoma County, who believes the return of circa-1998 wealth is more likely than romantic evenings in his hot tub, writes:

"I have a 10' x 10' concrete slab that was designed for a hot tub, but in these troubling economic times, we've decided to simplify and use the space for a vegetable garden. My question: Can I build a planter box directly over the concrete? And if so, how deep would it need to be to be successful? I'd rather not remove the slab; who knows, someday we may be back to ordering groceries from WebVan and toasting the new economy in the 'tub."

Raymond, your champagne dreams are as refreshing as a spring breeze. And who knows? Perhaps your windfall will come from cornering the market in microgreens or breeding the Next Big Thing in broccoli — in your new vegetable garden!

I absolutely think you can build a planter box on top of the pad, and here are a few things I would do to ensure success:

To keep all the plants within reach, make your planters no more than 30" wide (i.e. front to back) if you'll be accessing them from only one side, or 60" wide if you'll be able to access them from opposite sides.

Leave yourself at least 24" between planters for comfortable navigation.

Orient your planters along the east-west axis if possible (obviously this depends on the orientation of your slab).

Make the slab a heat sink by leaving the southern edge exposed; it will radiate warmth throughout the night, which should improve yields.

Although most of your veggies need only 6"-12" of root space (tomatoes and root crops will appreciate more), you'll garden more comfortably if the planters are 20"-30" tall. If you attach a trellis (to the northernmost planter edge), make sure its top doesn't exceed your reach.

Here's a quick sketch of one possible layout on your slab, two boxes at 48"L x 36"W x 24"D plus one at 120"L x 30"W x 30"D:



To prevent rot of both the boxes and the plants, improve drainage by doing the following:

Raise the boxes off of the pad by attaching cleats (e.g. ripped 2x4s) to their bases. Depending on how long you expect your economic recovery to take, you could use redwood (probably a 5-year lifespan) or a composite lumber (forever lifespan).

Make the bottom of the boxes permeable, i.e. leave gaps between boards. Again, to increase lifespan I would consider a composite lumber for the bottoms, and I would line the inside of the box with weed fabric — spun polypropylene — to keep soil from draining away as well. If you want to get really fancy, try building the bottoms at a 1%-2% slope toward one corner, so all the water drains to that point.

Fill the bottom of the box with a layer of drain rock, topped with weed fabric, topped with potting soil. Try to leave a planting depth of at least 8"; if you're building the raised boxes pictured, that would be about 6"-12" of rock.

Because you're creating such good drainage, your potting soil may dry out; try coconut coir as a sustainable alternative to peat moss.

I would use untreated redwood for the boxes. Your trellis could be of either redwood or copper pipe; and you may also want to consider building "cages" framed with wood, copper, or plastic pipe to protect your investment from critters.

Good luck, and happy growing. Please send photos of whatever you create! And when you are rolling in cash again, I accept your invitation for a soak in that hot tub.

Growing Our Own

In trying economic times, folks are inclined to grow their own produce. George Ball (of Heronswood Nursery, Burpee Seed Co., The Cook's Garden et al.) recently wrote that, despite declining sales of ornamental plants, "we’re awash with early orders of herb and vegetable seeds, transplants and fruit bushes." And yesterday we learned that the First Family is putting in a little plot as well. (Although no beets — yet one more way the President and I are alike.)

This really is great. If more of us grew more of our own food, it could solve a myriad of problems, not to mention easing our budgets. And: in order for growing your own to really pay off, you need to avoid the $64 tomato. One of my favorite planning guides is Square Foot Gardening by Mel Bartholomew; but there's no shortage of good ideas online.

Whether you're planting square inches or square acres, the key is to have fun with it. If you've got a technique or a plan that you're really proud of, please share it with us!

Best In Show

If you were following me on twitter yesterday you know I was at the SF Flower & Garden Show. It's an interesting show for a number of reasons: the new venue, the specter of finality (since lifted), and — I'm sorry, I have to say it — the meh-ness of the gardens themselves.

Why do people go to garden shows? In a word, for inspiration. We want to see the newest plants, the prettiest pots, the brightest flowers. We want to be captivated by bold visions and ooh and ah over their realizations.

(Now, a disclaimer: I have never exhibited in a show like the SFFGS. It is an extraordinary commitment of time, energy, goodwill and money, none of which I have in excess. And anyone who does undertake a display has my respect and admiration — regardless of my opinion of the results.)

Rebecca Coffman's outdoor indoor showerSo to my mind, there are two kinds of show gardens that really knock socks off: one is the garden you, the viewer, could actually implement at your own home but had never thought to. This is the triumph of creativity over reality, doing more with less, making your rooftop into a succulent paradise, using radiators for retaining walls, breaking rules of logic (but not of nature: there's no pretending that the purple Dodonaea will stay a cute little foundation shrub, no matter how cool it looks against the blue spruce). Last year Rebecca Coffman did a nice job bringing the indoors out, and Michelle Derviss took my breath away with her zen spa garden.

Livin' Cheap in BajaThe other type is the garden that you, the viewer, could never possibly implement because it has never existed before and can never exist again. This is the triumph of imagination over reality: doing more with more, creating soaring masterpieces that Kublai Khan would envy. The best example from my recent memory was Gary Gragg's 2006 pipe dream: you couldn't do this at home, you wouldn't, but it really engaged your imagination and inspired that "what if...?" feeling that gives designers like me the bum's rush.

At this year's show, I saw a bunch of pretty plants; I saw a lot of big plants crammed into small spaces; and I saw a lot of ideas — but not a lot that successfully made the leap to reality. I liked Studio Replica's oversize concrete pots. I loved Andrea Hurd's dry-stacked stone wall and arch. I was impressed with Tilden Landscaping's craftsmanship in stone, metal and wood. I was utterly confused by the Urban Garden from UC Berkeley students (hey "kids": show, don't tell). But I didn't see Xanadu; and only one garden really stayed with me after I had left: Rebecca Cole's "Sky's The Limit," which earned too many awards to list.

Alice has some nice images of Rebecca's show (as well as others) over at Bay Area Tendrils; and you can see and read Rebecca's own experience with the exhibit on her blog. The reasons I think it was successful are straightforward: she had a simple concept, executed with a simple palette of colors and materials. Period.
Rebecca didn't try to shove two acres of plants into 200 square feet. She didn't try to pretend that Ceanothus and Lavandula bloom at the same time. She used materials available to us all, creatively, artfully. And we ooh and ah, and go home to figure out how we might achieve a little of the same. In other words, she inspired us.

Brava, Rebecca. You truly are the best in show. And to every other designer reading this: how are you going to raise the bar over the next year?