Which? uses cookies to improve our sites and by continuing you agree to our cookies policy

Best Buy growing-bag watering system

By Adele Dyer

Stop your crops from drying out with this watering system. It's an easy way to give the ideal amount of moisture and fertiliser for a bumper harvest. 

Put us to the test

Our Test Labs compare features and prices on a range of products. Try Which? to unlock our reviews. You'll instantly be able to compare our test scores, so you can make sure you don't get stuck with a Don't Buy.

Best Buy growing-bag watering systems

Growing bags are great for greenhouse crops, as you can plant them directly into the bag. However, this does make it tricky to spot when the compost is drying out and to avoid overwatering them. For sensitive crops such as tomatoes, this can lead to diseases and disorders, including blossom end rot and splitting. 

We wanted to find out if any growing-bag watering systems make it easier to keep your plants well watered and healthy. We grew tomato and cucumber plants in a climate-controlled greenhouse and watered them using four widely available watering systems. We connected each watering system to two growing bags; one containing three tomato plants and the other three cucumber plants. 

We pre-mixed feed and used it to fill the systems' reservoirs. For those without a reservoir, we connected the drippers to mains water and a liquid-feed device until it had permeated through the bags. 

We monitored the plants' health, and harvested and weighed the tomatoes and cucumbers. We also assessed how easy the watering systems were to set up and use. 

Which? members can log in to view our recommendations below. Not a member? Trial Which? for £1 and get full access to these results and all our reviews.

Growing-bag watering system Our verdict Ease of use Yield Score
Compost non-member logo M **** ***** 92%

Heavy crops

The 15L reservoir built into this system holds a watering-can-full of ready-mixed liquid feed. Spikes covered with capillary matting strips pierce the growing bag and automatically draw moisture up into the bag as needed. 

An indicator tells you when to refill the reservoir, which, in our test, was around every two days once the plants were fully grown. 

It's very easy to set up and use, and helped produce the heaviest crops. 

Find out which growing-bag watering system we're talking about - log in or trial Which? for £1

SHARE THIS PAGE