What are the downsides of a greenhouse?
PESKY PESTS AND LACK OF POLLINATION. While having a greenhouse can help you control most of what your plants come in contact with, one or two plants carrying pests like whiteflies or other diseases can quickly spread to the rest of your plants, sabotaging your entire crop. Mistake #1: Sealing the Greenhouse Too Tightly While that sounds logical, this is one of the most common and damaging greenhouse mistakes. Without fresh air moving through the space, humidity builds up fast. Plants release moisture through their leaves, and soil stays damp longer in cold weather.
Can I put tomatoes in an unheated greenhouse now?
Reliable varieties include Gardener’s Delight, Sungold, and Moneymaker. Use water barrels for thermal mass and fleece on cold nights to protect plants without heating costs. Sow tomato seeds indoors in mid-March at 21-27°C. Transplant seedlings into an unheated greenhouse from late April once nights hold above 10°C. Sow tomato seeds indoors in mid-March at 21-27°C. Transplant seedlings into an unheated greenhouse from late April once nights hold above 10°C. The UK unheated growing season runs April to October, giving 8-12 weeks more harvest than outdoors. Reliable varieties include Gardener’s Delight, Sungold, and Moneymaker.
Can plants survive in an unheated greenhouse?
It’s definitely possible to grow without heat if you use cold frames and/or hoop tunnels inside the greenhouse. In my climate, venting the heat on sunny days would be essential, even on cold days. Imagine a car parked in the sun all day. On a still, cold night, an unheated greenhouse typically stays 2-5C warmer than outside. On windy nights, that margin shrinks because moving air strips heat from the glass faster. By dawn, the temperature inside an unheated, uninsulated greenhouse can be only 1-2C above the outside air.