How To Grow Tomatoes in Containers

If you are wondering how to grow tomatoes in containers, pots, grow bags and other planters, here’s an introduction to some of the containers available.

Growing tomatoes in containers and large pots is more popular than ever. Even if you have a small garden a container in a sunny spot can produce many tasty tomatoes all summer long.
Three Air Pots

Growing tomatoes in containers has a number of advantages over planting tomatoes straight into the garden soil or greenhouse border.

  • It is easier to keep your plants disease free.
  • You can grow tomatoes on the patio.
  • Plants can be moved around the garden if necessary.
  • Helps protect against ground level insects etc.
  • Great for bush varieties that can trail over the side of a large pot.

Growing tomatoes in containers is particularly suitable for bush varieties because of the height. Bush plants will reach up to about 24 inches in height (depending on the variety) making a large pot ideal.

Of course there are drawbacks to containers such as:

  • Plants need watering more regularly.
  • Stability – may blow over in strong wind.
  • Require more careful watering/feeding – Blossom End Rot can be a problem.

One consideration is the container size – some tomato varieties need more room for their roots than other varieties. For example, Red Alert and Oregon Spring will need bigger containers than Tumbling Tom and Garden Pearl. Also, filling a container with too many plants can have an adverse effect on the amount and quality of the crop.

A Few Types of Container:

  • Grow Bags
  • Tomato Pots
  • Air Pots
  • Dirt Pots
  • Auto Pots
  • And Many More!

Growing Medium
Potting soil, also known as multipurpose compost from the garden centre, can become compacted and shrink over time. This will remove air from the soil and have an adverse effect on the growth of the plant and the health of the roots below.

Adding perlite is of great advantage and helps the root zone retain air and provide the oxygen that the roots need for respiration (plant growth) and nutrient absorption.

A Mix of 50% potting soil and 50% perlite is regularly used.
How To Grow Tomatoes in Containers

However, the disadvantage with containers is that they dry-out quickly and lack of space – a combination of providing enough water when needed and allowing enough space when plants and their roots become fully developed!

In warm weather (hopefully!), tomato plants need plenty of water when they are fruiting, so keeping the containers watered can be a problem.

Watering can be a tricky business when it comes to tomatoes grown in containers.

The first aim should be to keep the entire root area moist.
The reason is that roots are only able to feed from areas of soil that are moist.
If half the compost that your plant is growing in is dry, food uptake may also be reduced by half.

If you’ve ever tried to water a pot plant that has very dry soil, you will find that the water runs straight through and out the bottom of the pot, leaving the soil almost as dry as before the water went in!

This can happen to areas of soil in containers too without the gardener realising what is happening beneath the soil surface.

If you water from above, give the soil a thorough watering once a week (depending on the weather), then allow to dry until just moist or slightly dryer. Keep the soil like this by watering moderately until the next thorough watering.

The smaller your container, the more regularly you will need to water – a hanging basket full of fruiting tomato plants could need watering up to three times a day in hot weather!

Roots need air too!
To develop well, roots need water, nutrients and air. It is easy to over-water tomato plants thinking that you are being kind but soil that is constantly soaking wet contains no air. The result is a poor root system resulting in slower growth and on a hot day, when more moisture is needed, wilting may occur because the roots haven’t developed properly.

You may also find that plants that haven’t been able to develop their root system … perhaps they’ve just been transplanted or haven’t experienced a full day of direct sunlight and become aclimatised … may also wilt. A spray with a mist of water will help them out.

More tips for containers.
Perlite is very helpful for drainage, soil aeration and water retention and is well worth adding to compost.

Water retaining gel also helps to reduce the frequency of watering. Perlite and gel can help keep compost consistently moist and help reduce blossom end rot.

Adding sharp sand to the bottom of large pots helps to stop them from being blown over in windy weather and aids drainage.

Don’t put too many drainage holes in the bottom of containers and pots because you don’t want water to escape before it has whetted the entire compost area. This also applies to grow bags where drainage holes should be made at either end rather than in the middle for the same reason.

When watering, avoid splashing the soil up onto the bottom leaves. Some soil borne diseases will infect plants more easily through the leaves than the roots. Removing the lower leaves of tall varieties can also help to avoid infections.

Tomato plants do not like to be watered with very cold water… let water from the cold tap warm up to air temperature or add a little warm water.

For more information on how to grow tomatoes in containers please visit

Check out the website tomato growing for more hints and tips about growing in containers.