Mini-Greenhouse / Grow House
Structure
A mini-greenhouse, often called a grow house, is a compact covered shelving unit for a patio, balcony or small garden. It provides useful protection for pots and module trays, allowing earlier sowing and a gentler start for young plants where a full greenhouse is impractical.
How it works
Its clear plastic cover admits sunlight and reduces wind and rain around plants. Shelves make efficient use of a small footprint, while the enclosure holds a little daytime warmth. The light structure offers limited frost protection and can become very warm in sunshine, so it is best treated as a flexible nursery space rather than a fully protected winter house.
Best for
It suits salad leaves, herbs, strawberries in pots and module trays of brassicas, leeks, flowers and annual vegetables. Use it to raise tomatoes, peppers and courgettes before planting them out, rather than to crop large plants permanently. It works especially well on a sheltered patio close to the house, where daily watering and ventilation are straightforward.
How to use it
Position it against a sheltered wall with good light, ideally where it will not be struck by gusts. Assemble it on a level base and anchor it securely to a wall, fence or substantial weights. Arrange plants so taller pots do not shade smaller trays, and leave the zip cover open on mild, sunny days. Close it before cold evenings, adding horticultural fleece over tender trays if frost is expected. Harden plants off gradually before moving them into open ground.
Tips
Wind is the main weakness, so check anchors after every storm. Avoid leaving the cover closed all day in bright weather, as seedlings can scorch or collapse from heat. Water little and often when trays dry quickly, but never allow pots to stand constantly in water.
Mini-Greenhouse / Grow House: frequently asked questions
How does mini-greenhouse / grow house work?
Its clear plastic cover admits sunlight and reduces wind and rain around plants.
How do I use mini-greenhouse / grow house?
Position it against a sheltered wall with good light, ideally where it will not be struck by gusts.
What is mini-greenhouse / grow house best for?
It suits salad leaves, herbs, strawberries in pots and module trays of brassicas, leeks, flowers and annual vegetables.
General guidance for UK gardens and allotments. Page updated 19 Sep 2026.