Mini greenhouses are smaller than full-size greenhouses, but big in usefulness! The term mini greenhouse can refer to several styles of greenhouse:
- A set of shelves for plants, with a plastic cover fitted over the top to protect them
- A very small conventional-shaped greenhouse, with a plastic sheet cover or rigid plastic glazing
- A lean to or closet-like greenhouse where access is “reach-in” but there’s much more space than the shelf-style units
- A cold-frame like structure
- Covered planter trays for starting plants from seed or cuttings
We’ll take a closer look at all these kinds of mini greenhouses in this article.
Shelf-Style Mini Greenhouses
Other mini greenhouses of this style come with 2 or 3 shelves instead of 4 – the 2 shelf versions are small enough to stand on a bench or table. The size you need depends on how many plants you plan to grow in them, whether seedlings, pot plants, tropicals, cuttings or overwintering herbs.
While these units are intended to be used outdoors on your deck or patio, they also work indoors to keep the atmosphere around your plants nice and moist.
I find a mini greenhouse like this most useful for hardening off the seedlings I start in my basement. Placed on the deck, right by the back door, mine is very convenient for opening and closing the cover, moving plants around to make sure they get even light, watering, and generally keeping a close eye on them. It allows me to expose the young plants gradually to the outside world, while taking up very little floor space, and in the summer I can take the cover off completely and use it for potted herbs and flowering plants.
|Gardman 7620 Compact Walk In Greenhouse with Shelves|
|Retail Price: $115.99|
|Amazon Price: $76.98|
Advantages include cheapness, and being portable – so you can use it on a deck or patio, or over a different garden bed at different times. This certainly beats moving all the soil out of a fixed greenhouse bed and replacing it, as some books advise you to do! It’s important to fix the greenhouse down well – as you can see, the model in the picture uses guy-lines and stakes, though on a patio or deck, weights would do the same job. You can also pack the whole thing away over the winter if needed, so no worries about it being damaged or blown away by winter storms.
One of my neighbors uses a small greenhouse like this for his tomatoes. Every year he plops the greenhouse over a different spot in the garden in the early spring and allows the soil to warm, plants his tomatoes a month earlier than he could if they were completely unprotected, gradually leaves the door open for longer as the weather warms, spends the summer picking great tomatoes while the cover keeps the rain and the blight off the plants, picks for a long time into the fall, then puts the greenhouse away for the winter until he chooses a new spot the next year. This is a great way to rotate your tomato crop to keep down diseases and pests.
Lean-To or Closet-Style Mini Greenhouse
They can be placed over plants growing in the ground to provide an excellent warm micro-climate for something like a dwarf peach tree trained against a wall, but they also work very well for tall pot plants like standard fuchsias or other tender but large plants. An important feature you can see in the picture is a vent at the very top, where the heated air collects. You can make this an automatic vent which will help to keep the temperature under control even if you can’t open the main door.
My mother has had a greenhouse like this for about 20 years on her backyard patio and it’s always full, summer and winter, even though she has a large sunroom as well!
Cold-Frame Type Mini-Greenhouse
Bear in mind that once you have a cold frame, you’ll find a million more uses for it that you would never have thought of, so although a small one is cheaper it may be better in the long run to buy as large a model as you can fit into your space and your budget.
Covered Plant Trays as Mini-Greenhouses
|Hydrofarm CK64050 Germination Station with Heat Mat|
|Retail Price: $34.99|
|Amazon Price: $20.30|
Either of these clear tops can be bought alone, or you can get them as part of a set with the seedling tray, cover, and peat pellets or cell packs to hold the plants. The best sets also include a heating mat which makes a huge difference when starting heat lovers like peppers, eggplant and basil.
|Hydrofarm MT10006 9-by-19-1/2-Inch Seedling Heat Mat|
|Retail Price: $24.95|
|Amazon Price: $15.70|