When the vegetable garden’s beds, as outlined on the coming season’s planting plan, are all spoken for and you wish there was just a little more space for a pepper plant or two or a small patch of that new lettuce variety, think pots. Vegetables in pots are a moveable feast. The pot that this year will grow lettuce in a shady corner of the perennial bed was used last summer to grow basil on the sunny porch steps.
Almost any container will work, provided it has drainage holes in the bottom and suitable capacity. Use the following list to determine the container size needed for various vegetables.
Vegetable, size, number of plants
Broccoli, 2 gallon, 1
Cucumber, 1 gallon, 1
Eggplant, 5 gallon, 1
Green onions, 1 gallon, 3-5
Leaf Lettuce, 1 gallon, 2
Parsley, 1 gallon, 3
Peppers, 5 gallon, 1-2
Radish, 1 gallon, 3
Spinach, 1 gallon, 2
Squash, 5 gallon, 1
Tomato, 5 gallon, 1
Turnip, 2 gallon, 2
There was a time when container gardeners had to make their own growing media, mixing horticultural grade vermiculite, peat moss, perlite and various mineral nutrients to produce a soilless mixture that would provide physical support for the plant yet drain well (garden soil drains poorly in containers). The only other options were packaged soil mixes that were generally too tight and held too much water, and thus drowned plant roots. Thank goodness those days are over.
These days there are some excellent soilless media for container vegetable production. I use either ProMix or one of the Fafard mixes, adding composted cow manure or worm compost as a nutrient source — one part compost or castings for every four parts soilless mix — and wetting the mixture thoroughly before seeding or transplanting.
I like to give all of my containerized veggies a shot of liquid fish emulsion once a month during the growing season, beginning a week or so after potting. My thinking is that the frequent watering necessary for container production rapidly leaches nitrogen out of the pot and it needs to be regularly replaced. I use half the recommended amount of the fish emulsion concentrate unless the plants tell me there is a definite nitrogen deficiency (yellowing foliage or no new growth) — too much nitrogen can delay flowering and fruiting.
Most importantly, avoid wetting the foliage of plants when watering since moisture on the leaves encourages plant diseases. When to water will depend on the container size, plant size and weather conditions, so you should check each pot every day. Use your index finger to see if the soil is dry about an inch below the surface; if so, water the pot slowly, letting the water seep into the soil, until you see some water emerging from the drainage holes at the bottom of the pot. This will ensure thorough watering.
I put our pots on large rocks or other surfaces that will allow excellent drainage of excess water. The drainage holes of pots placed directly on the ground can become plugged with soil or roots that grow out of the container and into the surrounding soil. Elevated pots are also less likely to attract slugs, which like to spend the day beneath objects resting on the ground.
Mulches can be placed on the surface of the container’s soil mix to reduce water loss. Keep in mind, however, that you may be providing another hiding spot for slugs.
Recognizing the growing interest in container gardening, vegetable seed catalogs and websites are giving more space to varieties selected for container culture. For example, the cover of this year’s catalog from The Cook’s Garden features ‘Cherry Stuffer,’ a two-inch sweet pepper ideal for container culture, while Territorial Seed Company is pushing ‘Patio Star Zucchini’ with a compact habit, half the size of regular zucchini plants yet bearing full-size fruits.
John Scheepers Kitchen Garden Seeds offers “The Terrace Container Garden”, a collection of seed packets, each a different vegetable variety suitable for pot culture. The collection includes ‘Parmex Baby Doll Carrots,’ ‘Ashley Cucumbers,’ ‘Little Orlando Eggplant,’ ‘Rubens Baby Romaine Lettuce,’ ‘Autumn Bell Peppers,’ ‘Milano Black Zucchini’ and ‘Super Sweet 100 Cherry Tomatoes.’
Finally, Pinetree Garden Seeds of New Gloucester, Maine, has devoted an entire page in its 2012 catalog to 14 different container vegetables and herbs, none of which are listed in the other catalogs. Pinetree’s list includes two eggplant varieties, ‘White Fingers’ and ‘Ophelia’ (deep purple fruits), two cucumbers, ‘Alibi’ and ‘Muncher,’ and ‘Bush Delicata,’ a compact form of my favorite winter squash.
Container gardening is a rapidly growing avocation. For me, growing a vegetable in a pot creates a moveable feast for both taste buds and eyes, a chance to try a new variety, a spot of color in the summer perennial bed. For many urban gardeners, containers are the only gardening option. Pots filled with vegetables, as well as flowering plants, are a common site on the balconies and patios of apartment dwellers. For parents and teachers, growing veggies in containers is a great way to introduce children to the joys of gardening.
Seed companies mentioned
The Cook’s Garden, www.cooksgarden.com
Territorial Seed Company, www.territorialseed.com
John Scheepers Kitchen Garden Seeds, www.kitchengardenseeds.com
Pinetree Garden Seeds, www.superseeds.com
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