Growing a kitchen garden

March 1, 2011

12:00 AM

I’ll let you in on a secret: The notion that you need a “green thumb” to successfully grow your own fresh, tasty vegetables? It’s a total myth.

Here in South Carolina, just about anyone with a backyard and a willingness to get his or her hands dirty can grow a small “kitchen garden” that will put home-grown food on the table year-round. All you need to get started this spring is a 4-by-4-foot plot of ground and our five-step plan for success.

Pick a sunny spot

Locating your kitchen garden close to the house makes it easy to monitor, tend and enjoy, but the first consideration should be exposure to sunlight. Most vegetables require 6 to 8 hours of full sun a day, and direct sunlight is particularly important to ensure summer crops such as tomatoes and peppers develop ample fruit. Avoid placing beds near large trees and shrubs. In addition to casting shadows on your plants, large tree roots can steal nutrients from your vegetables. Another consideration: Proximity to a good water source. Hoses and watering cans can get heavy if you have to drag them too far every time you tend your garden.

You don’t need a lot of space for a thriving garden. In fact, small garden beds—each no larger than 4 feet by 4 feet in size—are easier to maintain than large garden plots, and the square dimensions allow you to work the garden without stepping into the bed. As you gain experience and confidence, you can always add more beds, but for beginners, it’s better to have one or two manageable mini-gardens than one big garden that is hard to maintain.

Prepare the ground

Modern vegetables are highly domesticated plants that need pampering, primarily in the form of soil that’s healthy, full of organic nutrients and as light and loamy as you can make it. What do I mean by loamy? Think of the texture of good-quality potting mix. Chances are your backyard isn’t like that, so get ready to dig—or as gardeners say—to “amend” your soil.

Remove any grasses or weeds and thoroughly work the soil to a depth of 10 to 12 inches. Start by turning over shovelfuls of soil. Break up large clods of clay with the end of your shovel or a spading fork and remove any large rocks. Small beds can be hand-dug (it’s great exercise) or tilled with power equipment if hand-digging is too difficult. Now assess what you have. If your freshly dug plot is largely broken-up clay subsoil, you’ll need lots of organic material to lighten it up. If you have sandy soil, it’ll be easier to dig, but it also needs the addition of plenty of organic matter in the form of bagged compost, composted manure or topsoil from your local lawn and garden center. Either way, count on working in at least 4 to 5 inches of compost or topsoil. Spread this layer on the surface of your bed, and then mix it in with your shovel or spading fork to create a bed of rich, loose soil (remember that potting mix).

Compost and topsoil alone will not provide adequate nutrients to support vegetable production. You’ll also need to add organic, timed-release fertilizer. Carefully follow the label directions, and don’t overdo it. Adding too much fertilizer will result in excessive succulent plant growth that is attractive to pests and subject to disease. You may also need to add pelletized limestone to achieve a neutral, vegetable-friendly oil pH of 6.2 to 6.5. To determine precisely how much fertilizer and lime your soil needs for optimal growing conditions, have it tested by Clemson University’s Agricultural Service Lab (clemson.edu/agsrvlb) after you turn the soil and add compost, but before adding fertilizer and lime.

If the ground is hard and compacted, an excellent alternative to digging and amending the existing soil is to create raised plant beds. Smother the turf and weeds with a thick layer of moistened cardboard, then add a layer of compost followed by 10 to 12 inches of rich topsoil or a bagged, organic planting mix. This is the easiest and most dependable (but not the cheapest) way to get your vegetable garden off to a great start. There’s no need to contain the beds, but if you wish to make your garden more decorative, use wood, brick or stone edging.

Plant according to seasons

Thanks to our relatively mild winters, South Carolinians can rotate through cool-and-warmseason plantings and maintain a garden almost year-round. Early spring (March to early April) is a great time to plant lettuce, kale, mustard, spinach and other leafy greens that thrive in cool weather. If you plant today, you can harvest and enjoy them in time to replant summer vegetables like beans, tomatoes, peppers and squash. These warm-weather plants— tomatoes in particular—need nighttime air temperatures greater than 50 degrees to thrive, so as a general rule, it’s wise to wait until the third week of April to plant summer vegetables. For details on seasonal plant options, see “Growing seasons,” page 17, and consult Clemson Extension’s HGIC Factsheet #1256, "Planning a Garden” (hgic.clemson.edu/factsheets). It lists the best planting times for each region of the state.

For the best results, choose pest- and disease resistant varieties of seeds or transplants. Buy only fresh seed from established seed companies (I’ve listed some of my favorites online at SCLiving.coop) and shop carefully for transplants. Look for sturdy, well-grown transplants with healthy leaves and check the labels for information on resistance to disease, wilt and blight. When shopping for tomato transplants, for example, look for the abbreviations RN (which indicates resistance to nematodes) and V, F1 and F2 (which indicate resistance to wilt).

Follow the planting instructions on the seed packets or plant labels, and resist the urge to overplant—even a small garden can produce a surprising amount of produce. Trellises and supports for tomato and pepper vines will help maximize space in a small bed and increase productivity. Before you begin planting, map out your garden by dividing each bed into 16 1-by- 1-foot planting spaces. Each square-foot space can support one large plant (e.g., tomato, pepper, eggplant, cabbage, broccoli or summer squash), two cucumber plants or eight pole beans. Large robust tomato varieties will benefit from more space (2–4 blocks) and support for their vines with tomato cages or trellising. Smaller plants, like radishes, spinach, beets, lettuce, chard, carrots and parsley, can be sown directly into a 1-by-1-foot space and thinned to 12 to 16 plants per square foot through early harvesting.

Tend to your garden, naturally

Monitor your garden frequently for any pest and weed problems. In a small garden, low-impact control methods, like planting disease- and pest-resistant vegetable varieties, hand weeding and hand removal of insects are often all that is needed. You can prevent weeds and conserve soil moisture by keeping your garden mulched with an inch or two of chopped leaves, weed-free straw, dried grass clippings (not treated with herbicides) or weed-free compost.

Daily watering is required to get vegetables established from seed, but as the plants get larger water them less frequently in order to encourage deep, healthy root growth. Established vegetables with deep roots need watering only once a week, though in periods of drought or extreme heat—or any time plants look stressed and don’t recover overnight—you may need to water twice a week. And remember: Gently water the soil around the plant, not the plant itself.

Harvest early and often

Now it’s time to savor the sweet taste of success. Harvest your vegetables frequently while they are young and tender. The unsurpassed flavor of home-grown produce picked at its peak is a wonderful reward for all your hard work, so enjoy! For fun, you might even try a taste test, comparing your veggies to what’s available at the grocery store. You won’t believe the difference.

Once a crop is going downhill—when the vegetables become watery or over-mature—rip the plants out, amend the soil as needed, and plant something else. Quick-growing “fillers” such as lettuce, cilantro, edible flowers and greens are a good choice to plant if you need to wait out a change in seasons. Don’t be afraid to experiment, and, most of all, have fun with your very own kitchen garden.

Lisa K. Wagner , Ph.D., is the director of education at the S.C. Botanical Garden in Clemson and an avid home gardener. Read more about her passion for natural gardens at naturalgardening.blogspot.com.