If your tomato plants don’t give a bumper harvest, it might not be down to how you’re nurturing them. Instead, it might be the fault of a poor growing bag.
Which? Gardening has tested seven growing bags, and the good news is we found three excellent peat-free bags that gave us abundant harvests of cucumbers. In fact, these Best Buy grow bags gave us almost twice as many fruits as the lowest-scoring bags.
Discover which are the best grow bags.
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Best grow bags
Which? Gardening tests grow bags every year, as we know they’re an easy way for gardeners to grow tomatoes, cucumbers, aubergines, chillies and peppers, either in the greenhouse or on the patio.
Most of the bags we tested this year were peat-free, marking a huge turnaround from only a couple of years ago, when most growing bags were filled with peat-based compost, and many had a very high percentage of peat.
Handy tips on how to get the most from peat-free composts.
How to use a grow bag
Grow bags can be used in a greenhouse, but if you don’t have one, place them in a sunny spot such as on a patio.
- Roll the bag gently along the long side to distribute the compost evenly, then make a few slashes on the underside using a sharp knife. This will stop the bag from getting too wet when you water your plants.
- Cut square holes in the top of the bag, following the guide lines on the bag. The number of plants you can grow in one bag will vary depending on the size, so read the instructions on the bag.
- Your plants should be around 15cm tall when you plant them in the bag. Remember that tomatoes, cucumbers, chillies, peppers and aubergines aren’t hardy, so wait until around mid-May to plant up your bag if you’re growing outside. In the meantime, you can grow your plants from seed, using a Best Buy seed compost.
- Use a bamboo cane or plant support to train your plants while they grow. Remember to water regularly. During hot summer days when your plants are at their most productive you might have to do this at least twice a day.
- Plants need fertiliser to grow and ripen their fruits, so use a Best Buy tomato feed once a week unless the instructions on your grow bag tell you the compost contains enough fertiliser.
Find out everything about how to grow summer veg in our guides, including which varieties taste best and give the best harvests.