Home Gardening Center Tip Sheet: Growing Vegetables In Containers

By Sonia Uyterhoeven

·· Container Gardening ··

Growing Vegetables In Containers

Vegetables have traditionally been grown in the garden, but because of a plethora of new varieties it is becoming easier to shift your vegetable garden to the patio. Dwarf and midget varieties make it possible to create a vegetable garden on your windowsill.

Growing vegetables in containers has a number of advantages. It is sometimes the only option for people with small spaces. Container gardens are portable, they can be moved around to suit your personal taste or to compensate for changes in light and temperature. Vegetables grown in containers are less susceptible to soil-borne pests and diseases. Finally, it is a wonderful way to showcase your plants and keep them within easy reach.

There are also a few downsides to container gardening. The containers need frequent watering. Containers on rooftops and exposed areas will need to be protected from the intense heat of the afternoon sun and winds. Some vegetables do not fare well in the confined space, and a restricted root system can sometimes mean sub-par fruit production.

Several factors are involved in choosing suitable containers for you vegetable garden. As well as making an aesthetic choice for your patio garden, there are different cost, weight, and watering considerations you must consider when choosing different types of containers.

Vegetables grow well in terra-cotta pots. They are porous and have excellent drainage and air circulation, yet are heavy and fragile. Plastic containers and faux terra cotta pots (polyresin or polyethylene containers) are much lighter and are appropriate in situations where weight restrictions are a consideration. Non-porous containers are better at holding moisture and require less water, but do not provide the same drainage and air circulation as terra cotta. Both work well, they simply require different care.

Wooden containers and whisky barrels are popular for growing vegetables. Make sure that the wood is not chemically treated nor toxic to vegetables. Cedar, redwood, and synthetic lumber made from recycled plastic work well--they resist rotting and do not require staining. Grow bags and hanging baskets also provide good homes for vegetables.

There are many ‘self-watering’ containers on the market these days that dramatically cut back on your watering duties. These containers have a reservoir that gets filled with water that the plants can draw on when needed. These containers are an excellent choice for thirsty vegetables such as tomatoes.

When considering container sizes, the rule of thumb is the bigger the better. This is particularly true of vegetables that need space for good root growth--tomatoes, bush varieties of squash and cucumbers, eggplants, and peppers. Three- and five-gallon containers and half whiskey barrels make good, large containers. For shallow rooted vegetables such as radishes and lettuce, pot size is not as crucial. Pots can be eight inches wide and six to eight inches deep. Raising containers on bricks or some kind of feet is always a good idea to increase drainage and air circulation.

There are many recipes for soil-mixes for container plants. Find the one that works best for you. Garden soil does not work in containers: it is too dense, does not provide enough drainage, and may contain soil-borne pests and diseases. Container potting mixes need to be lightweight, have good drainage, provide support, and hold water and nutrients. For an easy recipe, try three parts potting mix with one part bagged compost. Potting mixes are either soilless mixes (consisting primarily of peat moss) or soil-based mixes (containing pasteurized soil). Soilless mixes are lighter, while soil-based mixes are better at holding water and provide more support for large plants.

At planting time, add a slow-release fertilizer to the soil. Start fertilizing with a liquid feed mid-season. Reapply every two or three weeks. Containers are watered so frequently that they require more fertilizer than plants in the ground. Potting mixes also do not hold fertilizer as well as topsoil. Follow directions for slow-release fertilizer and use a slightly diluted rate for liquid fertilizers.

Containers need frequent watering, often daily on a sun-scorched terrace. Adding water retaining polymers or hydrogels (starched based gels that retain water) help to decrease the watering load. These gels hold water until the soil mixture needs it. Some people swear by them, others do not. Always follow instructions when using these products. Mulch is another effective way to decrease moisture loss. Compost, straw, shredded bark, and even sea shells or pebbles can be used as mulch for your containers.

Vegetables planted in containers are susceptible to pests and diseases just like your other plants. Using clean containers and choosing disease resistant varieties go a long way preventing problems. Inspect you plants for insects. If you have an insect or pest problem try a homemade remedies before reaching for store bought chemicals. Try spraying the plants with soapy water, or try this recipe: Place one onion, two to three hot peppers, and two to three garlic cloves in a blender. Add to one gallon of water, add a few squirts of dish soap and then let sit over night. Strain, shake, and apply to your plants with a pump spray.

Ultimately, good watering, feeding, and maintenance practices will help ensure healthy plants. Vegetables grown on terraces may need to be covered with a shade cloth if the afternoon sun is too intense in southern or western exposures. Warm patios may be fine for the heat lovers, such as tomatoes, peppers, or eggplants. Lettuce and many of the root vegetables will need some protection.

Finally, the fun begins. What will you plant? Loose-leaf lettuce, tomatoes, peppers, eggplants, zucchinis, bush beans, and cucumbers do well in containers. There are plenty of tomatoes to choose from; dwarf varieties, cherries, and determinate varieties all do well. Try 'Patio Princess,' 'Tumbling Tom,' 'Husky Gold,' 'Sweet 100,' 'Roma,' and 'Better Bush Improved.' For small disease resistant varieties of bush cucumbers, try 'Salad Bush,' 'Spacemaster,' or 'Fanfare.' Watermelon 'Bush Sugar Baby' grows on 3 1/2-foot-long vines that can be trellised. How about cantaloupe 'Honey Bun' or pumpkin 'Baby Bear' and the white 'Baby Boo' for the adventurous gardener? Or carrot 'Short n' Sweet' and 'Little Finger' intermingled with 'Baby Oak' lettuce for the conservative gardener? There are plenty of choices for everyone.

Download this Tip Sheet.

·· Container Gardening ··

Generous support for the Home Gardening Center has been provided by Kenneth and Ellen Roman.