More in Outdoors
The biggest vegetables go in the biggest containers. Put tomatoes (Image 1), squash, zucchini or eggplant in larger containers near the back. You can use transplants purchased from your garden center or start with seeds. The minimum size container for a regular tomato plant is five gallons, but the bigger the better. Ten-or 15-gallon pots are best.
All tomatoes are labeled either 'Determinate' or 'Indeterminate' based on their growing habit. For container planting, it's usually best to choose determinate tomatoes, since these are more compact and take up less space than indeterminate tomatoes.
Tomatoes will need staking as they grow, so place bamboo stakes in each corner of the container (Image 2). By placing the stakes in the container early on, you don't risk damaging the tomato roots as you would if you waited until later. You can use any kind of stakes, but bamboo is particularly attractive for use on a patio.
In containers, you can plant a 'Black Beauty' eggplant (Image 1). It's an heirloom variety that gardeners having been growing for almost a hundred years. Each plant should yield five or six large purple fruits. Most types of eggplant will grow well in a container, so choose any variety. A three-gallon pot is the minimum size for an eggplant shrub, and a five-gallon pot is even better.
To start vegetable seeds in containers, proceed just as if you are planting them in the ground. Zucchini is easy to start from seed and is usually ready to harvest just 55 days from sowing. One good variety is called Spacemiser. It produces loads of full-sized zucchini on plants that are smaller than most other zucchini plants. Plant three seeds per container and then thin them to one plant per three- or five-gallon container.
Many cucumber plants sprawl too much for containers, but a few varieties are short and compact and perfect for pots. A variety called Spacemaster is excellent for container gardens (Image 2). It will grow well in a pot as small as three gallons.
In general, root vegetables such as leeks, onions, radishes and beets require less sun than do fruit-bearing vegetables. Fruit-bearing vegetables such as tomatoes need at least five or six hours of full sun a day to grow well; root vegetables, on the other hand, will typically grow well with three or four hours of direct sun.
Leeks grow well in containers, as long as the container is at least 12" deep. Place seedlings 4" apart in a three- or five-gallon pot (Image 1). They'll be ready to harvest in two months, after which you can replant for another crop.
Beets grow easily from seed (Image 2) and are ready to harvest 50 to 60 days after planting. Sow a variety such as 'Chicago Red Hybrid' beet seeds in a five-gallon container, planting the seeds 1/2" deep and spacing them 1"-2" apart. When the seedlings get 4" tall, thin them so that the beets are growing 6" apart.
The most shade-tolerant of all vegetables are leaf crops such as purslane, lettuce, spinach, kale and cabbage. They can be grown in areas that get just a few hours of morning or afternoon light every day. Purslane is a European green that will take warmer weather than most other lettuces or greens. It grows well from seed and is good in salads and sandwiches.
Vegetables will give a patio a nice green backdrop, but for season-long color add some flowers. In keeping with a vegetable-garden theme, it's fun to plant edible flowers. (Keep in mind that although they're enjoyed by most people, edible flowers may cause food allergies in some individuals. But even if you don't care to eat them, edible flowers make a beautiful and safe garnish and are a great way to dress up a dinner plate.)
To add bright yellow and gold to the garden, plant pot marigold or calendula. Pot marigold's daisylike flowers have long been used as a yellow food dye, and the petals can be sprinkled on salads or desserts. But take note: pot marigold is different from the more commonly found African marigolds, which are bitter-tasting.
Another good flower choice is pineapple sage. In the summer it has beautiful red blooms that attract butterflies. Its edible leaves and blooms have a slight pineapple taste.
With the vegetables planted and the patio dressed up with a few flowers, the main concern is keeping everything watered and fertilized until time to harvest. On a hot patio in the middle of summer, containers dry out quickly and need to be watered nearly every day, sometimes even twice daily. You can hand-water, but if you're out of town more than a day or two, you may come home to plants that have wilted or died.
Purchase a patio irrigation kit that uses 1/4" vinyl tubing. Select a kit that comes with a timer, pressure valve and all the tubing and drippers you'll need to set up a patio system (Image 1). You can find patio kits at garden centers or through mail-order stores.
Attach the timer to the outdoor faucet nearest the patio (Image 2). The timer will let you set your own watering schedule, watering anywhere from twice a day to once a week, from 10 minutes to several hours at a time.
Following the kit's directions, insert the pressure valve into the tubing adaptor and add the filter (Image 3). Run the tubing over to the container, tucking it out of sight behind the containers. For each container, create one branch line.
To make a branch line, cut the vinyl tubing with a knife and insert a tee connector (Image 1). Reattach the tubing on each side of the tee, and put a new length of 1/4" tubing along the tip of the tee.
Most kits came with two types of emitters or drippers, such as a one-gallon-per-hour inline dripper and a half-gallon-per-hour dripper, which attaches to the end of a branch line (Image 2). You can use one or more of each dripper, or a combination of them, for each container. The drippers are held in place with a small stake that comes with the kit (Image 3).
After a branch line has been run to each container, close the tubing with an end cap.
After planting, add a 1/2" layer of mulch around the top of each container (mulch keeps the pots from drying out too quickly and prevents soil from splashing up onto the plants). To start, adjust the irrigation system to water for a half-hour every day. To see whether the plants are getting the right amount of water, stick your finger about 2" into the soil at the side of each container when you make your daily round of the garden. If the soil is too dry or too wet, adjust the timer up or down accordingly.
Container plants respond especially well to water-soluble fertilizers, so give regular doses of liquid fertilizer to keep the plants productive. Water the transplants with half-strength liquid fertilizer as soon as they are planted. For containers in which you're starting seeds, simply keep the soil moist with tap water. Once the seeds germinate and the plants get true leaves, start them on the half-strength liquid fertilizer as well.
Once the plants get larger, apply full-strength liquid fertilizer once a week. When selecting a fertilizer, check the label and choose a balanced solution that contains micronutrients and trace elements.
On your daily check of the garden, keep an eye out for bugs. Plants in containers can attract hornworms, borers, beetles and all the other pests that plague vegetables planted in the ground. But with container gardens, pests are easy to spot and control. You usually can handpick any insects that you see, and should rarely, if ever, have to spray.