[big green bloke]

some of my red onions have bolted about a quarter any hints on how to stop it happening yours big green bloke

[John]

I've got the same with my Japanese onions. The only thing I can think is that the weather isn't helping. It's been so unseasonably warm.

I cut off the flowering stems as they appear and use those onions first as they don't store well.

[Aidy]

Think your right there John, its been so dry. Some of my cabbages were starting to head up nicely then bag, just went to seed almost over night.

[Trillium]

You've got it, John. The early heat and dryness signals the plant to go to seed rather than to grow. Like you, I simply cut off the flowering stem as early as possible and use that onion first. Happens with all the onions, not just reds.

[waddecar]

I changed to autumn sown sets 3 years ago and susceptibility to bolting is much reduced. So far this year no reds have bolted and only 2 yellow ( out of about 80 of each). Also I'll be able to lift them early July and get some late French beans in their place.

[WG.]

I also plant onion sets in autumn but can only ever find the Japanese varieties.  My problem is that around half of them seem to die.

Which varieties do you autumn-plant please?  Do you get good survival rates?

[waddecar]

I get my autumn sets from Edwin Tuckers, but Marshalls also do them I believe. Yellow variety is "Radar" and red variety is "Electric". I am also trying shallot "Echalote Grise" from an autumn planting for the first time this year- they are going well so far.

Survival rates for yellows has been about 100% every year, the reds seem to be prone to fungal attack so I usually discard a fair few every year before planting. In fact this year I advised Tuckers of the fungal incidence and they refunded the cost. Those that are planted seem to have good survival rates too - and the  red bulbs are so small that you get around 100+ I guess in 250gms so discarding a few is no hardship.

I garden on the coast so although wind and rain is a problem in winter we do not get severe frosts. Oh and I use raised beds so no waterlogging.

Hope this helps

Brian

[WG.]

Fantastic Brian, thank you for the comprehensive reply.

[David.]

Picked the first 2 seed heads off my electric reds today. I leave the stem so I know which ones to use first. No problem with the Radars (yet).