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How do I grow sweet peas in cardboard?
Q I am planning on sowing sweet peas in toilet roll tubes this year. What is the best way to do this – do I need to cut and fold the bottoms of tubes across, or can I just fill tubes as they are?
Thomas Moug, via email
A The reason for growing sweet peas in toilet rolls is to encourage them to establish deep roots which are necessary for a long and healthy growing season.
The deepest roots will obviously develop in the full-length tube but you then need to consider that you will have to plant the whole thing.
If you have freshly turned soil and lots of elbow room then this will be easy, but if you are having to plant in among other things, digging such a deep hole may not be quite so straightforward.
Choose the maximum depth of tube that you can accommodate!
The roots of the sweet pea seedlings should penetrate the cardboard of the tube once they are planted in the ground but I think it would be best not to ‘close’ the bottom of the tube which might provide something of a barrier and prevent the roots continuing to go deep into the soil.
If you need to find a way to keep the soil in the
