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How to grow tomatoes in a growing bag

You will need

  • 2 - 3 tomato plants
  • 60 or 75 litre bag of multi-purpose compost
  • Knife or scissors
  • Hand fork
  • Trowel
Do it: June (or May in a greenhouse)
At its best: harvest from July to September
Takes just: 30 minutes


Greenhouse tomatoes are often planted in grow bags, but outdoor crops can also be grown in this way too. A good alternative to a specialist grow bag is to try planting in a 60 or 75 litre sack of multi-purpose compost. This will provide your plants with a larger rooting area and stop them drying out in hot weather, which is better for the plants and means less watering for you.

Either plant the tomatoes direct in the compost or use a growing ring to increase the amount of compost the roots sit in, which is said to increase the amount of water and nutrients available to each plant and therefore increase crops.

How to do it


Soak pots of young tomato plants in a tray of water for an hour to ensure the compost is fully moistened, which will help reduce root damage during transplanting. Lay the growing bag in a sunny position and shake it to dislodge any compacted compost inside. 


Cut a slot out of the bag to expose the compost for planting into. Use a hand fork to further dislodge compacted compost if necessary.


If planting direct in the compost, use a hand trowel to create a planting hole and gently knowck the plant out of its original pot. Place your tomato plant in the planting hole, replacing the compost and firming gently. Allow two plants for a 60 litre bag of compost,or three plants for a 75 litre bag. Water in well.


If using a growing ring, push this into the compost before planting the tomato plant. Then plant as you would otherwise, taking care to water well and firm the compost around the plant.


It's a good idea to grow companion plants - such as French marigold, Tagetes, to deter whitefly from attacking your plants. Place one plant into the planting hole next to the tomato.


One of the benefits of using a growing ring is that when you water the plant, water is directed straight to the roots and doesn't run off the surface of the compost. Make sure you water regularly and, once flowers appear, feed weekly with a high-potash fertiliser to increase your crop.

Discuss this project

Talkback: How to grow tomatoes in a growing bag
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crystal2010 24/11/2011 at 15:27

excellent ..would like your advice due to getting tomato blight last year for the first time in my greenhouse Im not sure how to proceed this year ..I mormally grow them in the soil should I use a grow bag or dig out some soil and replace it with new what do you advice? look forward to hearing from you margaret stead

jollyoldgran 24/11/2011 at 15:27

I planted the seeds that I got free with your magazine 27 seeds 26 really robust plants I put three in a grow bag in my conservetory yesterday I intend to try three more in a growbag outside and another lot in the ground, so that means I still have 17 plants to find a loving home soon as the weather improves I'll set to work

annejn 24/11/2011 at 15:27

What about growing in the garden? Bob Flowerdew's books have ggod advice on making a plastic tent for them...

tony2 24/11/2011 at 15:27

I grew some toms last year but did not have much success but after reading up on the site I've got 14 beautiful seedlings of three types all from seed from GWM and hopefully will have some lovely toms this year.

jonjack 24/11/2011 at 15:28

I recently tried growing tomatoes in one of those upside down tomato garden planters and I was really pleased with the results.

I have written a post about it on my blog as well as a how to for making your own upside tomato planter.

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