Container Vegetable Gardening for Balconies and Small Spaces

Growing in containers lets you control the soil, drainage and location. You are not dealing with compacted yard soil, and you can move pots to follow the sun. Clemson Cooperative Extension notes that vegetables grown for their fruits, such as tomatoes and peppers, generally need at least five hours of direct sun a day but do better with eight to ten, while leaf and root crops tolerate partial shade. UNH Extension says almost any vegetable can be grown in a container if you choose miniature or bush varieties.

Look for three things: enough depth, drainage holes and a material that suits your site.

Clemson Extension says most plants need containers at least 6 to 8 inches deep. Larger fruiting crops such as tomatoes and peppers need much more room, and for tomatoes both Clemson and UNH say a five-gallon bucket with drainage holes can work. Drainage holes are essential so roots do not sit in water. If a container has none, drill holes in the bottom or along the lower sides.

Clay, wood, plastic and metal can all work. Clemson notes that porous clay pots lose water through their sides, so they need watering more often. Dark containers and metal can heat up in strong sun, so on a hot balcony keep them away from reflected heat where you can. If you reuse buckets or other containers, UNH Extension advises avoiding any that previously held chemicals.

Use a potting mix made for containers instead of soil from the garden. Clemson Extension says garden soil is usually too heavy for a container, and UNH recommends a soilless mix of a water-holding material such as peat or coir with perlite or vermiculite for drainage. The mix should feel light, not dense or clumpy.

Frequent watering washes nutrients out of the pot, so container crops usually need regular feeding. Clemson says plants in a pre-fertilized mix typically have enough nutrients for about eight to ten weeks, after which fertilizer is needed every two to three weeks. UNH suggests starting a dilute liquid feed about once a week after plants have grown for three to four weeks. Follow the label on whatever product you use.

These crops are generally practical in pots. Choose compact, bush or patio varieties where the label offers them.

Loose-Leaf Lettuce and Salad Greens

Leaf crops tolerate partial shade better than fruiting crops. UNH Extension lists cut-and-come-again greens such as mesclun, spinach, Swiss chard and arugula as good choices for containers. A window box or shallow planter can hold them.

Compact Peppers

Look for compact or patio cultivars and give them full sun and a large pot. If your plants flower but do not set fruit, see the pepper troubleshooting guides linked below.

Bush Beans

Bush types do not need a trellis, which makes them easier to place on a balcony or patio than pole beans.

Herbs

Many herbs, including basil, chives and parsley, grow well in pots. They are an easy first crop and need only modest space.

Cherry and Patio Tomatoes

Clemson Extension recommends compact cultivars labeled patio, balcony or bush for containers, since indeterminate types keep growing until frost. Our balcony tomato guide covers pot size, support and common problems.

Containers dry out faster than ground beds. Clemson says daily or even twice-daily watering may be necessary in hot weather. Check by pushing a finger into the mix: if it is dry an inch or two down, water until it drains from the bottom. UNH advises watering thoroughly instead of giving small sips.

Expect a learning curve. Plants may bolt early in heat or produce less than a seed packet photo suggests, and you will learn what your own spot allows over a season.

Yellowing lower leaves can come from overwatering or from nutrients washing out of the pot. Check drainage first, then feed. Slow growth despite regular watering often means the pot is too small or roots are crowded. If plants lean toward one side, rotate the container so all sides get light.

• Clemson Cooperative Extension, "Container Vegetable Gardening"
• Clemson Cooperative Extension, "Tomatoes in Containers"
• University of New Hampshire Extension, "Growing Vegetables in Containers"