Cold Greenhouse

we used to heat our greenhouse when we started seed sowings around February we used an old fashioned heater that burned solid fuel  wood or coal though cast pipes we had to light it in the early morning and keep it going all day then at night we had to supplement the heating with a calor gas heater and although the cast pipes heated under the staging worked out very well it proved to be to expensive to run

so we now start our sowings around early March in a cold greenhouse its a bit later than i would like but we haven't lost anything by doing this and if the temp goes down then we cover up with fleece not a problem and all our veg seed is greenhouse raised

and our seed potatoes there kept in bags in a frost free place till the weather gets a tad warmer then we box them up in chitting trays and stack them in the potting shed again cover the trays with fleece if temp falls never had any problems doing this and we never have any supplementary lighting or heating

I use a cold greenhouse for much of my seedling production.  I’ll start with a few early sowings of summer cabbage towards the end of this month, plus broad beans and probably some spring onions as well.

February (depending on how cold it is) will be more sowings of brassicas, onions, leafy greens.

March and April are still variable, but you can sow most hardy veg.  You might have to hang on for tender stuff like french and runner beans, tomatoes and the like.  Indoors generally means around 20 degrees C for germination, so a cold greenhouse is not always warm enough.  They are not cheap but a indoor propagator with grow lights could be the answer.  Something like this :

https://www.suttons.co.uk/garden-equipment/all/geopod-heated-propagators_mh4723

I shuffle my hardy stuff out into a cold frame as it gets to a decent size, so it might be worth looking into those as well or make your own.  You can also do a lot to protect tender stuff inside a greenhouse.  I have one of those cheap 4 tier plastic covered mini greenhouses set up inside mine early on in the year, plus fleece on hand.

You can chit spuds in there, but you do need to make sure they don’t freeze or cook.  I use my shed now as it has a window, but in the past I have laid out seed spuds in trays on the benches from February onwards.  I used a double layer of fleece underneath them, then had a double layer to cover them.  That still lets enough light in to chit them.  If it suddenly goes warm, you need to get them uncovered fast and out of the sun. 

So not ideal for everything, but with a bit of imagination you can make most things work for you 

While on that subject about leeks, do you need a deep seed tray to start them off in

Yes, cat litter trays are ideal..

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