Wednesday, May 12, 2010

Veggie Gardening in Containers by Donna Duffy

The number of people who grow vegetables at home has increased dramatically over the past few years. But what if you are limited on space? Vegetable gardens require lots of square footage, don’t they? Well, not necessarily. Some vegetables will be perfectly content to grow in a container if a few basic principles are followed.

1.     Match the container with the vegetable you want to grow. Tomatoes do well in a large, deep container (at least 12”) that provides stability when the plant gets tall, and also has room for strong root growth. Beans, on the other hand, do well in a long box, at least 12” wide and 8” deep (choose pole beans). Carrots, chard, leaf lettuce, beets and peas all need a container that is at least 8” deep. Regardless what you are growing, make sure the container has never contained any kind of toxic material. Container veggies must have drainage. If your container doesn’t have holes, you could put a layer of rocks on the bottom of the container, and then plant your veggies in a container “insert” – a pot slightly smaller than the outside container. Be sure the insert has drainage holes. Remember: a larger container will make your veggies easier to care for and will allow you to provide a larger supply of water and nutrients.

2.     Be savvy about soil. Avoid using soil directly from your garden – it’s probably too full of clay and may contain pests that will cause problems later. Purchase potting soil at your local garden center instead. 

3.     Pick plants purposefully! Not all veggies are well-suited for containers. When you are shopping for veggies (or seeds), look for descriptors such as “compact”, “patio” “bush” or “determinate”. If you are planning on growing tomatoes, the following are good choices: Patio, Pixie, Tiny Tim, Saladette, Toy Boy, Spring Giant. The CSU Extension Garden Notes #724 has a long list of veggies appropriate for containers: http://www.ext.colostate.edu/mg/gardennotes/724.pdf

4.     Water, water, water! Growing vegetables in containers requires a bit more attention than growing ornamentals. The quality of most container grown veggies will improve if a constant supply of water and nutrients is provided. Without this, most vegetables will lose flavor, become tough, and perform poorly. In the heat of summer, your container may require watering every day (maybe even twice a day). Always apply enough water that the excess drains out. Avoid standing water by draining any saucers under the container (tip: use a turkey baster if the pot is too heavy to lift).

5.     Add nutrients.  Because the container will limit the root spread of your veggies, a regular supply of fertilizer is critical for maximum production. At the time of planting, add timed release fertilizer if the soil doesn’t already have it. Throughout the growing season, add soluble fertilizer according to label directions. More is not better! If you over-fertilize, you’ll have a lovely crop of leaves and stems instead of veggies.