QUESTION TIME

GOT A FRUIT OR VEG PROBLEM? ASK KG FOR HELP

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SPRING ONIONS FAILING IN POTS

Q. I attempted to grow spring onion Pompeii and White Lisbon from seed by direct sowing in pots, using a mix of multipurpose compost and John Innes No 2 with perlite for drainage. The seeds were sown at the correct depth and germinated as expected. They grew well for a while, but then started to die back. Only a few survived and those failed to grow on properly. I tried again, sowing more thinly and watering less. Growth was better, but the plants remained very small. I'm unsure whether the soil wasn’t rich enough or if something ate the roots, but I can't seem to replicate the success I had growing spring onions years ago.

Christina Feltham

A. This is a very common spring onion problem, and you've already done several things right, which helps narrow down the cause. It’s very unlikely to be pests. The issue is almost certainly a combination of compost nutrition, pot culture and feeding.