I have been thinking about getting a greenhouse. Last year we used the conservatory at our house to start seeds and grow tomatoes. It was perfect, but we moved house and don’t have that sort of place anymore.
If I had plenty of room I would do a polytunnel, as that would be the most cost-effective way to cover a large space and would allow both propagation and all-season growing. However, a polytunnel would cover the entire width of my allotment and would waste some space around the edges, as you need a margin between the wall and your neighbour’s plot for maintaining the tunnel. Plus I’m not sure how nice a polytunnel would look in a walled garden.
My neighbour has a greenhouse which was just blown to pieces in a storm. It is the aluminium variety you get at garden centres, with glass panes. I’m not sure I want to go that route having seen what a mess was caused when it blew down.
There are two suppliers of steel-framed greenhouses in Ireland. One makes a greenhouse which is basically a steel shed with a clear corrugate polycarbonate cover. Kayla and I saw one at a garden centre in Carlow last weekend. It looks indestructible and has the right dimensions. It would seem to suffer from two defects: not very airtight (lots of gaps at the door), and the polycarbonate is single sheet and clear: good for propagation but not as good for growing, which favours diffused light. I could definitely make it work with some weatherproofing.
The other supplier makes a similar frame but with double-walled polycarbonate sheeting. It looks more airtight and would likely be better insulated. It also comes with an automatic air vent which I think would be indispensable. I haven’t seen a model yet but would like to visit a display centre in the coming month.
I think either one would do, now I need to get permission from the allotment owners to put one up. I’m very much looking forward to a place to get out of the weather and start some seeds.