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How many weeks to sow before last frost date?
Randommoose1
Posts: 99
in Plants
Hi,
I want to sow some tomatoes, Cosmos and Verbena Bonariensis, possibly a few other things but these are the priority. According to the Garden Focussed website my last frost date (6 out of 7 years, not average 50/50) is the last week of April. I only have a single small south facing windowsill for the seedlings so, though the small seed trays I have will fit, potted on plants might be tricky to fit many. How long to the plants need to stay inside from seed sowing until being the right size to harden off outside? Once I know that then I can count back from last frost week to work out when to sow them. The packets just say sow Jan-April or similar which is no help!
Thank you for any help!
I want to sow some tomatoes, Cosmos and Verbena Bonariensis, possibly a few other things but these are the priority. According to the Garden Focussed website my last frost date (6 out of 7 years, not average 50/50) is the last week of April. I only have a single small south facing windowsill for the seedlings so, though the small seed trays I have will fit, potted on plants might be tricky to fit many. How long to the plants need to stay inside from seed sowing until being the right size to harden off outside? Once I know that then I can count back from last frost week to work out when to sow them. The packets just say sow Jan-April or similar which is no help!
Thank you for any help!
0
Posts
I don't sow anything much until about now. It's mid May before anything can either go outside permanently, or into the growhouse with tomatoes. That gives me around 8 weeks from sowing, which is pretty much ideal for my conditions.
I also don't have loads of suitable windowsills for endless pots and trays, so the timing is important. I need to be able to put hardy stuff outside, or in the growhouse until the toms go in, when they're at a suitable stage - ie tough [ and big ] enough to be able to withstand it.
By mid April, I can also sow more hardy annuals, and they can be started outside or in the growhouse instead of in the house, because it's suitable for germination and the subsequent potting on etc.
When in doubt - always sow a couple of weeks later to make life easier.
I live in west central Scotland - not where that photo is...
That is useful to know about 8 weeks growing time works for you. I've not sown anything yet this year as I don't want to deal with it being too early and plants getting leggy or too big, I would rather it be later and smaller. Previously I always bought tomato plants but the GW magazine came with seeds so I thought I would give some of them a try. I've never grown flower seeds inside before, only a few direct sow things outside (Phacelia and Nigella are the only two that worked).
It's what the conditions are like further ahead in the year that determines how easy it is to get plants outside successfully.
We're less inclined here to get frosts in May, but it also isn't particularly warm, consistently enough, through April, so plants don't really start growing well until May. We can get all sorts in April - rain/sleet/snow and high winds, so all of that is a factor in how well they come on.
Tomatoes are too hit and miss for outdoor growing because the summer weather isn't consistent enough either, although the last couple of years has definitely been different, and that may make a difference in future. They need reliable overnight temps to do well.
A south facing wall is often ideal for protection, and the eaves of a house can shelter small plants from excess rain too, so that's generally a good site. I often use the space beside the back steps of my house, as we're quite elevated. I can tuck small plants in there on the side that's out of the prevailing wind/rain, but my bench is great for that - allows moisture and light in, but keeps the worst of the weather off them
I live in west central Scotland - not where that photo is...