Home & Garden writer Holly Hayes — that would be my spouse — and I have been running a little experiment in urban farming with a series of raised beds that emphasize vertical gardening. We built them over an unused driveway space that is the sunniest spot in our backyard.

The experiment has been, on the whole, quite the success. We have a flood of exotic squash, colorful peppers, four varieties of beans and a rainbow of chard. Oh, yeah, and Ambrosia melons that are to die for. As has been the case in many backyard farms this summer, our tomato crop has been lagging, thanks to the cooler-than-normal weather, but the towering plants are starting to pump out fruit.

We have received a flood of e-mails from readers about their very clever ways to make the best use of small garden spaces. Here are some of the best:

At the trough

We installed a very efficient garden last year and everybody has said they haven't seen anything quite like it. We simply take livestock watering troughs and use them for planters. They are extremely easy to install.

I have five tanks: one 5-foot round, one 3-foot round and three 2 feet by 8 feet. I placed them on a gravel bed and punched about 20 holes in the bottom for drainage. I then put about a foot of 2- to 3-inch river rocks; 4 or 5 inches of gravel, filling the rest with a combination of local native soil and planter mix. (This settles rather quickly,

so I had to add 6 to 12 inches after a few months.)

This year, we have eight varieties of tomatoes, five of peppers/chiles, okra, basil, two varieties of strawberries, squash (vines hang down over the edge of the bins to the ground), sugar peas and carrots. One bin was dedicated to blackberries to contain the new shoots but I have since moved them to another contained area. (I harvested enough blackberries to last all year.)

In the winter, I will have broccoli, various lettuces, sugar peas, carrots and winter squash.

I got the bins at a feed and pet supply for $150 to $175 each.

I initially put in this system because of a bad back problem because it allows me to garden without leaning over. Also, there have been no snails, slugs or bug problems.

I never knew gardening could be so easy. I guess the produce I have (or will have) harvested this first year will just about pay for the initial investment.

— G. Craige Edgerton, San Jose

Rock collection

My husband and I downsized a few years ago. No more watering my huge garden by hand, just a little garden in the sunny back yard. But the gophers! No garden.

But after a time, spurred on by the nationwide gardening bug, I wanted another garden. The requirements: 1) get rid of the gophers; 2) raised bed; and 3) use all those gorgeous rocks inherited from my husband's rockhound grandmother, gathering dust at the side of the house. I had always wanted a rock wall, but the real answer came when a new Arts and Crafts house with a rock foundation was completed across the street.

I asked the newly out-of-work artist builder to make me a rock-faced garden area lined with hardware cloth featuring all the rocks that we had collected through the years: fossils from childhood, weathered stones from England, river rocks and petrified wood from Oregon, geodes and obsidian from Nevada. It's gorgeous and the back faces an alley so that I've shared the beauty of it with the neighbors.

— Stella Sexmith, Santa Cruz

Frontyard gardening

My wife and I decided last year to start growing some herbs and vegetables. To my neighbors' surprise, we pulled out all the shrubs in a section of our front yard between the driveway and the entry way. It's an odd shape: roughly 30 feet long, 1 foot wide at the curb and 6 feet wide near the house.

Initially, my kids and I turned up all the soil with a shovel and planted some perennial flowers in the winter. Come spring, we filled it out with vegetables and other color. It is now a flourishing garden, to the delight of folks that drive by. Plus we have an array of herbs (sage, oregano, thyme, basil and cilantro) and vegetables including tomatoes, hot peppers, blueberries, squash and eggplant.

I am soooo NOT a green thumb. I just took a crack at it and it mostly has been a success.

— Bruce Hartman, San Jose

Small spaces

My garden is in a very small space: 2 feet wide by 12 feet long in three raised boxes, with an additional box across from it that is 12 feet long, 2 feet wide, and 2 feet tall for my fruit trees. I have my tomatoes in pots on my front porch, where they can get the most sun. Vertical gardening is definitely the way to go in such a small space. I created mine based on instructions in the book "All New Square Foot Gardening" by Mel Bartholomew, which also includes a recipe for making your own potting mix that has worked really well.

My kids and I did the same thing at their school, building six 3 foot by 3 foot boxes and making the potting mix together a couple of summers ago. (I was 6 months' pregnant at the time with my third child, so it was quite the sight!) I plant the boxes with the kindergarten classes so they can see how plants grow and learn how to maintain a garden (it's unfortunately not as big a part of the curriculum as I'd hoped, but I keep trying).

— Missy St. Pierre-Sands, Santa Clara

Rethinking the driveway

We did (almost) the exact same thing this winter, turning the driveway (the only sunny spot in the yard) into a vegetable garden. Actually we tore up all of our cement and didn't put in as many garden boxes as you did (but there's room for more!)

I currently have five kinds of tomatoes, two kinds of peppers, summer squash, mint and basil. We have harvested the red chard (it was burned in that May heat wave but came back) and put in strawberries. The tomatoes are going strong. Yum!

This is the first year I've put in a veggie garden. We never had enough sun and finally figured out that the useless driveway space was perfect.

— Lisa Hettler-Smith, San Jose

Making it work for kids

I'm a middle school science teacher in Livermore, and always add a garden to each school I've worked at. I was really surprised this year about how much my students enjoyed eating the snow peas that they grew. I thought that, by seventh grade, they would be too "old" to show this enthusiasm. That's the beauty of gardens; they always add magic.

What resonated from your article was the point about raised beds being wheelchair-friendly. We have many special-needs kids at our school and I am now determined to make a garden that they can participate in, starting with the planning. If nothing else, I'll bring the Earth Boxes I currently use to a higher level. Thanks for the inspiration!

— Regina Brinker, Livermore

A return to gardening

I don't usually write to the newspaper, but your garden struck a wonderful chord with me.

Having had back surgery this spring, I knew I needed to stay close to home this summer as I recuperated. So a dear friend helped me build a raised garden — raised to my elbows actually (I'm 6-foot-1) — in a delightfully sunny spot behind my prefab home.

I got so excited to start a garden after 25 years of not having one, that I planted corn, tomatoes, cilantro, carrots, pumpkin, cucumbers, zucchini and spinach. I even wheeled in a little red wagon in which I planted strawberries. It turns out that the snails can't climb the wheels of the wagon.

— Janet Hascall, Sunnyvale

Grow where planted

When it comes to small-space gardens, I think our dealership (John P. Carlsen Volvo in Palo Alto) has everybody beat. Our "garden" is only a half-inch wide — the table just inside the door is where we eat lunch.

Apparently some tomato squeezed out of somebody's sandwich and a seed got lodged in the gap between the asphalt and the wall and sprouted. We have problems with Ailanthus sprouting out of the same crack, I was about to yank the plant out when I noticed that it had yellow flowers on it.

Closer inspection revealed that it had already set four tomatoes that were about the size of peas. We installed a drip irrigation system (gallon jug with a pinhole in bottom, fill it with water and it drips) and it started growing better. Don't know what variety it is, or how they taste. We have a couple that are almost ready to try.

— John Pelmulder, Palo Alto