DIY Mini Greenhouse

No need to apologise, I was worried you were thinking of starting seeds now.

I sow tomato seeds indoors in our utility room next to the boiler, in mid March. It is a steady 22C ideal for germination. I have to check at least once a day and when they have germinated I move them to a cooler room with growlamps. I don't try and heat my whole greenhouse, in the past I've sectioned off an area with bubble wrap and a heated propagator to keep them growing. It's worthwhile investing in a max/min thermometer to keep an eye on temperatures in the greenhouse. I have a remote sensor with the display unit indoors, anything below 10c is bad news for tomato seedlings. Also higher temps are just as bad, a very sunny windowsill or greenhouse can quickly rise to 35C or more in early spring.

Other veg are hardier, I still start germinating them the same way (an airing cupboard would also work). Brassicas and salad leaves can be moved into a frost free greenhouse to grow on before planting in my allotment.