If there are fairies at the bottom of my garden, then they live in 5 star accommodation. A couple of years ago I saw a picture of a Grow Dome, a geodesic dome greenhouse that makes it looks like the Eden Project has dropped off one of its offspring in your garden for a play date,

The Grow Dome is designed to be as self-sufficient as a greenhouse can possibly be. The geodesic shape makes the structure very strong – able to withstand a pounding by the wind and heavy snowfalls.  The polycarbonate double-glazing is unbreakable (a big plus in my garden, which is regularly bombarded with balls from the house over the road) and gives the plants a lovely soft, diffused light that they love.

When I ordered my Grow Dome, the smallest size available was 15 feet in diameter – you can now get a 12 foot model – and this is what I have because it’s the only one which would fit. In the US, where they’re made, there are people with 32 foot models and beyond. I’ve even heard from a guy who lives in his, and they’re used for swimming pools as well as indoor gardens.

A 15 foot Grow Dome comes with 3 automatic vents, powered by hydraulic lifts. When the sun comes out, they open the vents for you to keep the temperature inside the Dome more bearable. One is in the roof, and the other two are lower down on the sides.

The entire north wall of the Grow Dome is covered in Reflectix insulation, which looks like silver bubble wrap. It not only keeps heat in, but reflects light back into the greenhouse. The Dome itself is supported on a low wooden frame, which has foam insulation hidden inside it.

I haven’t fitted mine yet, but you get a solar powered fan that can be used as part of a under soil heating system, pulling warm air from the Dome down under the soil through plastic piping. In a very cold climate this could be a considerable bonus, but I haven’t yet seen a need for it here in the UK. The fan will be useful to keep air moving in the winter though, when the vents are held shut to keep them safe in high winds.

Putting the Grow Dome together was a labour of love, to say the least. It took us a long time to get started, because we had to clear a bramble thicket at the end of the garden first. Putting the wooden frame together was easier than we thought it might be, but the whole construction process was quite painful. If we move and I have the money to buy another Dome then I would definitely pay someone else to put it up for me. If you have trouble putting together flat pack furniture then assembling a Grow Dome is not for you!

I built a large raised bed in the front of the Grow Dome out of large concrete blocks, which will add to the thermal mass, but you can use anything you want. I have a second, lower, raised bed under construction in the middle. Whatever you put in the middle of the Grow Dome has to be low enough for plenty of light to reach the ponds.

My Grow Dome became ‘fully functional’ (with a raised bed and filled ponds) at the end of August 2007. It was too late to stock the ponds with plants before the winter, but perfect timing for sowing and planting winter vegetables. Almost everything I planted or moved into the Grow Dome has survived the winter (so far, I’m writing this in January!). The Oriental vegetables (Chinese cabbage, Pak Choi and Tatsoi) are doing very well and we’re eating those now. My kale plants were on the small side before the start of winter but are healthy and will be ready for a head start in spring. Pilot peas are rapidly outgrowing their twiggy supports and my saffron crocuses are enjoying the frost-free conditions that remind them of their Mediterranean home.

Coriander plants which were moved into the greenhouse before the first frosts survived and even ran to seed, despite the fact that on very cold nights the temperature in the Dome does drop below freezing. The coldest I’ve seen it was -5ºC; there was ice forming on the ponds but no plants were harmed.

All-in-all, I’m happy with my first Grow Dome growing season. There’s not as much light in the winter as I had hoped – this is an urban area and there’s too many buildings in the way. That means the temperatures aren’t as high as they could be, and the plants don’t grow as fast. The Grow Dome is south-facing, for maximum possible light, but it seems as though light is going to be the limiting factor in winter growth. With the vents closed for the winter there isn’t much ventilation and I need to go out on nice days and prop the door open for a little while to get some fresh air in there. Fitting the solar powered fan will also help.

I’m currently building the second raised bed and planning my crops for spring and summer. I should be able to get some really early salad crops in before the summer plants – tomatoes, peppers and some more exotic experiments – take up the bulk of the room. I’m also hoping for a bumper harvest from my dwarf nectarine, originally container-grown and now living in the lap of luxury next to the ponds. I just hope the fairies don’t steal all the fruit!

This article is reproduced with kind permission of Emma Cooper.
All photo copyright belongs to the author and may not be preproduced without express permission.