I have had a few folk saying them are having trouble germinating cleome seeds. This is understandable…cleome seed is not the easiest to germinate for your cut flower garden.
There is a great difference in opinion as to when to sow and at what temperature they desire before they will join the party. The one thing most folk agree on is that cleome seed requires fluctuating temperatures…lows of around 3 degrees and highs of about 20 degrees.
Previously I have made this happen by sowing early in the greenhouse…around about March…this way the trays will get the low temperatures no problem…the issue is they have to wait an awfully long time before they get the highs….(I know the feeling). This can mean that the seed rots away in the weeks they are sitting in the cold and damp.
This year I tried sowing some later…in April…(And also sowed a tray today as an experiment) …the ones I sowed in April have been reasonably successful….about 10 plants from a sprinkling of seeds on a module tray…but…well…it’s not amazing is it?
HOWEVER…having spoken to a selection of the best flower farmers from here to Auckland, and I have found another method…thus:
Sow in mid April..put the tray in a poly bag and put it in the fridge for two weeks….then back into the greenhouse….and all will be well…(it does not work to just put the seeds in fridge…they need to be damp and in the growing medium)
Now this is probably too much of a faff for most of us…so I conclude that you are better sowing late and accepting that the germination rates won’t be brilliant…but of course you can sow more thickly…and these can be big plants…having 20 plants would be LOADS.
…don’t be afraid my seed loving friends…feel the fear and sow it anyway.
Find Cleome seeds and more…in the Higgledy Seed Shop.