Growing vegetables in containers
Pots, soil, sun and the best crops for small spaces
Find the sun
Warm-season crops like tomatoes, peppers, eggplant and squash need 6–8 hours of direct sun a day. Cool-season leafy crops like lettuce and spinach manage with 3–5 hours.
Containers let you put each crop exactly where the light suits it.
Choose big enough pots
Bigger pots hold more moisture and dry out more slowly. Here's a rough guide.
- Tomatoes: at least 5 gallons (19 L) per plant; full-size kinds do best in 8–10 gallons (30–38 L).
- Peppers, eggplant and cucumbers: 5 gallons (19 L) or more, about 12 inches (30 cm) deep.
- Beans, beets, chard and carrots: 4–6 gallons (15–23 L), 8–12 inches (20–30 cm) deep.
- Herbs, radishes, spinach, salad greens and peas: 1–3 gallons (4–11 L), 4–6 inches (10–15 cm) deep.
- Every pot needs drainage holes, and no gravel layer in the bottom.
Soil and food
Fill pots with potting mix, not plain garden soil, which is too dense for containers.
Frequent watering washes nutrients out, so feed regularly. Many gardeners use slow-release fertilizer at planting, then a water-soluble feed every 2 to 3 weeks, following the label.
Water often
In hot, dry weather, containers may need water every day, and small pots even twice a day. Check them daily, and water until it runs out the bottom.
Steady watering reduces blossom end rot in tomatoes and peppers, which is mostly caused by soil swinging between wet and dry.
Placing your pots
Dark containers in full sun can get hot enough to injure young roots. Clay and wood pots dry out faster than plastic.
Wet soil is heavy: a 20-inch (50 cm) pot of moist mix can weigh 100 pounds (45 kg). Check that a balcony can take the load.
Best crops for pots
Tomatoes, peppers, eggplant, green onions, beans, lettuce, squash, radishes and herbs all grow well in pots, and potatoes do well in grow bags. Look for varieties labeled bush, dwarf or patio. Melons, corn and sweet potatoes are much harder to grow in pots.
Related plant problems
Sources
- University of Maryland Extension: Growing Vegetables in Containers
- University of Maryland Extension: Types of Containers for Growing Vegetables
- Clemson HGIC: Container Vegetable Gardening
- Texas A&M AgriLife Extension: Vegetable Gardening in Containers
General guidance, not a diagnosis. Written by PlantWiz in our own words from the sources above.