Unexpected frosts have claimed their first victims. Creeping through the glasshouse, under some fleece and into a propagator, two thirds of a seed tray of Taiyo seedlings brown, dead. Frost is a strange beast, striking indiscriminately, ignoring the seed trays towards the back of the staging but there is a difference between these seed trays and those caught by the last frosts.
Last year we started to bring in module seed trays, to save time, and we have noticed some differences early on in the growing this year. The smaller modules, though great for raising plug plants, are for us, prone to being hit by frost. We've noticed it this year and and last. We think it is down to the quantities of compost used in each module, the smaller the module, the less is needed in comparison to the old fashioned seed trays or 3-5 inch pots. This means if a frost hits these trays, it will act almost like an ice cube tray, the less quantity of soil in a module, the easier it is to get cold, to literally plummet in temperature and freeze regardless of whether we have covered with fleece or in one case last year, bypassing the paraffin heater and killing an entire tray of cosmos. It's a domino effect, as one module freezes it cools those around it and they in turn freeze. We're happy to use the larger module trays but may have to think twice about the smaller module trays unless we can somehow bring bottom heat to these trays without running electricity to the glasshouse. If you have any ideas on this, do let us know. We have time to resow our sunflowers and some have survived in the tray, so not all is lost to the last frosts. April can be the cruellest month but it is also the month when the garden bursts back into life.
What have we learnt? #saveourskills
- Spring doesn't always means that frosts are over.
- It's important as growers that we are vigilant for frosts and that means watching the weather report.
- Fleece doesn't always protect your seedlings and if in doubt bring them indoors.
- Small module trays unless kept relatively warm can be prone to freezing.
- That saving time doesn't always mean that you get better crop.
- That losing a tray of seedlings can set you back a week or two but in spring that is not the end of the world, as we have time to sow another tray.