The Coastal Gardener:

It’s a few minutes before 7 a.m., the neighbors are asleep, and I’m staring at six cubic yards of decomposed granite that was just dumped on my driveway.

With my wheelbarrow and shovel, I’ve calculated that it will be 71 trips from the front driveway to the back yard, where I plan to spread this pile of rock. If all goes as proposed, that’s where I will install a garden dedicated to California’s native plants.

I killed the lawn there about two months ago. A couple of weeks ago I mowed the dead, brown thatch as low as I could, raked it vigorously with a steel rake and mowed it again, then repeated the rake-mow process a third time. Last week I got my exercise on the back end of a six-horsepower rototiller as it pulled me around the garden, chopping up the remaining grass remnants and blending them into the soil below. Four or five passes with a big gas rototiller, more than 2,000 square feet, is a lot of work.

As I explain to those who ask, I don’t have a garden per se; I have a laboratory. Actually, I don’t have one laboratory, I have several small laboratories. One is for succulent plants, one for edibles, one for tropical shade plants, one for Mediterranean plants, one for my large potted-plant collection. And if I can move this 16,000-pound pile of granite, one for my California native plants.

A laboratory is where experiments and research takes place. So that’s how I approach my individual laboratories. These small laboratories, you could also call them research plots, are further divided into even smaller outposts where I can test plants and experiment a bit; a rock garden of California native plants, a South African protea garden, a South American bromeliad garden, a winter bulb garden, a vegetable garden, a citrus garden, a California meadow garden and even a native shade garden. Not one big garden; many small gardens.

The gardens all have their own season, character and personality. Soil, irrigation and nutrition are vastly different from one of these laboratories to another. Tons of silica sand in the succulent garden, loads of forest humus in the tropical garden, manure and compost in the vegetable garden, and now a small mountain of decomposed granite for the native garden.

My small tropical garden gets lots of summer water while the native garden will receive almost none, the Mediterranean garden just a little more.

Vegetables get water year-round, but the bulbs only seasonally. The tropical garden thrives in the summer and fall, while the native garden will flourish in the winter and spring. Several gardens, all with different needs.

To me, the most intriguing aspect of a garden is in appreciating plants as collections and in learning how different plants belong together; how one plant complements another.

I don’t design gardens as much as I organize gardens. I don’t choose my favorite trees, then my favorite tall shrubs, some medium and low shrubs, a pretty ground cover or two, add in some nice perennials, a little lawn, a few annuals — and then stir it all together.

That kind of a garden is common. It might look pretty for a while and it might even impress the neighbors, but when you spend a lifetime with plants, you learn that something is wrong.

Olive trees just shouldn’t be with geraniums; agapanthus and boxwoods should be strangers.

Ficus, lavender and bougainvillea are fine plants as individuals, but they just shouldn’t be garden bedmates.

But back to my looming native plant garden. Here I am, just after sunrise, with a wheelbarrow and a shovel. The truck driving away just dropped a huge pile of ground rock on my driveway.

For the rest of the day I’ll be hauling and spreading this gritty granite amendment, 100 pounds of gypsum, two jars of beneficial microorganisms and six pounds of concentrated humic acid to my backyard soil.

Sunday, I’ll let the rototiller drag me around for a few more hours and, if I’m right, I’ll end up with a decent soil for my native plant laboratory. No fertilizer and no planter mix or organic amendment — not for these plants.

Next week, I’ll contour the soil a bit and create some raised areas where I can build some elevation into the now flat landscape.

Then, I’ll bring in a few tons of rocks and boulders and set a couple hundred flat stones in place to create a pathway through the new laboratory.

In two weeks the native plants will arrive, with names unfamiliar to most.

What garden? My laboratory’s construction is under way. Soon the experiments will begin.

Ask Ron

Question: I’ve heard about Pat Welsh’s new book. Is it out yet, and what’s the book’s name?

Jill

Costa Mesa

Answer: The queen of local gardening, Pat Welsh, has authored a new, much anticipated book. It is called “Pat Welsh’s Southern California Organic Gardening.” It is scheduled for publication in late November 2010. Put it on your Christmas list now, no local gardener should be without it.

ASK RON your toughest gardening questions, and the expert nursery staff at Roger’s Gardens will come up with an answer. Please include your name, phone number and city, and limit queries to 30 words or fewer. E-mail stumpthegardener@rogersgardens.com, or write to Plant Talk at Roger’s Gardens, 2301 San Joaquin Hills Road, Corona del Mar, CA 92625.

RON VANDERHOFF is the Nursery Manager at Roger’s Gardens, Corona del Mar.