Time to kit out the greenhouse! It’s not long now till planting out time, and when you have tomatoes and cucumbers bursting out of their pots ready to go the last thing you want to be doing is fiddling about setting up grow bags and pots or putting in supports. Get everything ready in plenty of time and it’ll all be there ready and waiting.
I have two greenhouses: one has open borders, really the best option for greenhouse growing as it allows the roots to drill down into the ground and reach at least some natural soil moisture. Your plants are less dependent on you for water and feed – and they generally grow that bit better, I find.
But the other greenhouse is under a big old holly tree: this doesn’t cast any shade, as it’s on the north side, but it does suck all the juice out of the soil, leaving it dry as a bone and nutrient poor too. I have tried growing in the borders in this greenhouse and plants always struggle no matter what I do.
So since I don’t want to cut down the holly tree, my only choice is to get them out of the ground and into pots instead. You have two options: seriously large containers – at least 45cm across – which can be expensive, and if you’re buying new they’re carbon-hungry to make, too. Or you can go for grow bags - but these are hard on the environment in other ways as they’re made from single-use plastic. On their own, they’re also too small to contain enough compost for a tomato plant so you’re stuck with doubling up to make them work – and that means yet more plastic.
There is one other way. Making your own grow bags might sound a bit eccentric but it’s actually very straightforward: all you need is some secondhand hessian sacks (available cheaply from online auction sites) and very basic sewing skills. The real gamechanger with these, though, is that plants do better in them: I think it’s something to do with the fact that roots emerge from the sides and are naturally air-pruned rather than circling. Whenever I grow in biodegradable single use pots I’ve observed this: plants are just happier growing that way.
Anyway: so here’s how you make a grow bag out of a hessian sack. Enjoy!
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