Container gardening is how most people grow their first vegetables — on a balcony, a patio, a doorstep, or a sunny windowsill. It works, and it works well, provided you match the vegetable to the container and accept that pots need more water and more food than garden beds. This guide covers vegetables container gardening properly: which vegetables grow in pots, the right container size for each one, what soil to use, how to water and feed, and the mistakes that catch beginners out. The timings and spacings below use published ranges for common vegetables, which vary by variety, climate and soil, so treat them as a guide. As with everything in this guide, check your local extension service for advice suited to your area.
The big advantage of containers is control: you choose the soil, you move the pot into the sun, and you keep slugs and weeds at bay more easily than in open ground. The big disadvantage is also control: a pot dries out fast, heats up in the sun, and holds only as much food as you put in it. A tomato in a pot is entirely dependent on you for water and feeding in a way that a tomato in the ground is not. Once you understand that trade-off, container growing becomes straightforward. Choose the right pot, fill it with good compost, water often, feed regularly — and you will eat well from a very small space.
Which vegetables grow well in containers
| Vegetable | Minimum pot size | Depth needed | Notes |
|---|---|---|---|
| Lettuce | 6–8 inches wide | 6 inches | Shallow-rooted; sow little and often |
| Spinach | 6–8 inches wide | 6 inches | Fast; pick outer leaves |
| Radishes | 6–8 inches wide | 6 inches | Ready in 25–40 days; sow direct |
| Green beans (bush) | 12 inches wide | 10–12 inches | Bush types suit pots; climbing types need a tall support |
| Tomatoes (bush/dwarf) | 14–18 inches wide | 14 inches or more | Needs a large pot; one plant per pot |
| Peppers | 12 inches wide | 12 inches | Warm and sunny; one plant per pot |
| Cucumbers (bush) | 14–18 inches wide | 12 inches | Bush types suit pots; needs regular water |
| Zucchini (bush) | 18–24 inches wide | 14 inches | One plant per large pot; very thirsty |
| Carrots (short types) | 10–12 inches wide | 10–12 inches | Choose short or round varieties; deep pots only |
| Beets | 10–12 inches wide | 10 inches | Thin to 3–4 inches apart; eat the leaves too |
| Kale | 12 inches wide | 12 inches | One plant per pot; pick leaf by leaf |
| Onions (from sets) | 10–12 inches wide | 8 inches | Space sets 4–6 inches apart |
Lettuce, spinach and radishes are the easiest container vegetables because they are shallow-rooted, fast, and happy in small pots. Lettuce is ready in 45–60 days and spinach in 40–50, and both can be picked leaf by leaf for weeks. Tomatoes are the most rewarding container vegetable but also the most demanding: a tomato plant needs a large pot, 14–18 inches wide, one plant per pot, and daily watering in hot weather. Carrots need depth above all — a shallow pot gives you short, stubby roots, so choose short or round varieties and a pot at least 10–12 inches deep. Avoid the vegetables that need the most room: sweet corn needs a block of plants to pollinate properly, pumpkins and butternut squash sprawl across 48–72 inches, and parsnips need deep soil for 100–130 days. The growing guide for tomatoes and the growing guide for lettuce cover the two most popular container vegetables in detail.
Choosing containers and soil
Almost anything that holds soil and has drainage holes will work: plastic pots, terracotta, fabric grow bags, wooden crates, even a bucket with holes drilled in the bottom. The two rules are drainage and size. No drainage holes means waterlogged roots and rot, so drill holes if there are none. And bigger is almost always better: a large pot holds more water and food, dries out more slowly, and gives roots room to grow. A tomato in a 5-gallon pot will outperform the same plant in a 2-gallon pot every time.
Fill containers with a good potting mix, not garden soil. Garden soil compacts in pots, drains badly, and can carry disease. A mix of compost, coir or peat-free potting mix with some perlite for drainage is ideal. The potting mix recipe guide explains how to make your own, and the soil volume calculator works out how much mix you need. Raise pots slightly off the ground on feet or bricks so water can drain freely, and use saucers only in very hot weather — standing water rots roots. Dark pots heat up more in the sun than light ones, so in hot climates choose light-coloured pots or shade the pot itself while the plant gets the sun.
Watering containers: the daily job
Containers dry out far faster than garden beds, and watering is the single most important container job. In hot weather a tomato in a pot may need water every day, sometimes twice a day. Water in the morning, water deeply until it runs out of the drainage holes, and check again in the evening. A pot that feels light when you lift it is a pot that needs water. Mulch the surface with straw or shredded leaves to slow evaporation, and group pots together so they shade each other and create a damper microclimate.
The most common container problem is uneven watering, and tomatoes show it first: irregular watering causes blossom-end rot, the dark, sunken patch on the bottom of the fruit. It is not a disease but a calcium problem caused by the plant being unable to take up calcium when the soil swings between wet and dry. Keep the soil evenly moist and it rarely appears — the blossom-end rot guide explains it in detail. Self-watering pots and drip irrigation on a timer are worth considering if you are away from home during the day. The watering calculator helps you plan, and the vegetables watering guide covers vegetable water needs in full.
Feeding container vegetables
Potting mix holds only a limited supply of food, and every watering washes some of it away. Container vegetables need regular feeding — far more than the same vegetables in the ground. Mix a slow-release fertiliser into the potting mix at planting time, then feed with a liquid fertiliser every one to two weeks once plants start growing strongly. Tomatoes, cucumbers and zucchini are heavy feeders and benefit most from regular feeding; lettuce, radishes and spinach need much less. Beans and peas fix their own nitrogen and need little feeding at all.
Do not overfeed. Too much fertiliser produces lush leaves and few fruit, and can scorch roots in a pot. Follow the packet rate, feed after watering rather than onto dry compost, and stop feeding lettuce and leafy vegetables a week or two before harvest. The fertiliser calculator and the vegetables fertilizing guide cover rates and timing, and the fertilising vegetables guide is the general reference.
Sun, spacing and support
Most vegetables need full sun — at least six hours of direct sun a day — and containers let you chase it: move pots to follow the sun through the season, and move tender plants under cover if frost threatens. Leafy vegetables such as lettuce, spinach and kale cope with a little shade, so put them in the shadier spots and save the sunniest places for tomatoes, peppers and cucumbers. Give each pot room for air to move around it; pots crammed together stay damp and invite disease.
Support matters for tall container vegetables. Tomatoes need a stake or cage from the start, before they flop over. Climbing beans need a tall cane or trellis. Cucumbers can be trained up a trellis, which also keeps the fruit off the ground and saves space. The plant spacing calculator helps you work out how many pots fit your space, and the vegetables spacing guide gives the spacing for each vegetable — remember that the spacing in the table above is the distance between plants, and one large plant per large pot is the rule for tomatoes, peppers, zucchini and cucumbers.
Common container mistakes
- Using pots that are too small, especially for tomatoes and zucchini.
- Using garden soil instead of potting mix, so pots drain badly and compact.
- Forgetting drainage holes, so roots sit in water and rot.
- Watering a little every day instead of deeply until water runs out of the bottom.
- Never feeding, so plants run out of food halfway through the season.
- Overfeeding, so plants produce leaves and no fruit.
- Cramming pots together so air cannot move and disease spreads.
- Growing vegetables that need too much room, such as sweet corn or pumpkins, in pots.
Most container mistakes come from treating a pot like a garden bed. A pot is a small, fast-drying, fast-emptying world, and it needs more attention — more water, more food, more checking — than the same plant in the ground. Give it that attention and it will repay you.
Frequently asked questions
What is the easiest vegetable to grow in a container?
Lettuce. It is shallow-rooted, fast at 45–60 days, and happy in a small pot. Radishes at 25–40 days and spinach at 40–50 days are close behind.
How big a pot does a tomato need?
At least 14–18 inches wide and 14 inches deep, one plant per pot. Smaller pots dry out too fast and the plant suffers — check your local extension service for varieties bred for containers in your area.
Can I use garden soil in pots?
It is not a good idea. Garden soil compacts in pots, drains badly, and can carry disease. Use potting mix, and the soil volume calculator to work out how much you need.
How often should I water container vegetables?
In hot weather, every day — sometimes twice a day for tomatoes and zucchini. Water deeply in the morning until it runs out of the drainage holes, and check again in the evening.
Do container vegetables need feeding?
Yes, regularly. Potting mix holds little food and watering washes it away. Feed with a liquid fertiliser every one to two weeks once plants are growing strongly, and follow the packet rate.
Related guides
For more vegetable help, browse the guides hub and the growing guides hub, and try the soil volume calculator and the watering calculator. Good next reads are the vegetables beginner guide, the vegetables raised bed gardening guide, and the vegetables watering guide. And as always, check your local extension service — local advice beats any general guide for your soil, your weather and your varieties.