Gardening – Snug in the greenhouse

In the darkest depths of winter there is nowhere in the garden that I’d rather be than cooped up snugly in my greenhouse. It can be howling a gale, teeming with rain or crackly with frost, and I’m dry, warm and happy.

As are my plants. This year, I’ve really concentrated on creating a near-perfect environment for my plants to bask in. My little old glass-covered 2×3 metre greenhouse has had a full makeover, with sheets of twinwall polycarbonate replacing the glass. At the same time, I’ve installed automatic vents, using surprisingly cheap vent openers purchased on Trade Me, which automatically open and close with temperature changes.

Not quite so cheap to buy, but no cost to run, is the solar-powered drip irrigation system I also found online. This nifty little system waters the plants according to how much sunlight is received each day, so will change with the weather and the seasons. I expect it will pay for itself handsomely as I’m not the most reliable or diligent of waterers. Previously, most of my greenhouse crops wilted.

To capitalise on the extra heat retention of the twinwall plastic, I’ve covered the ground with old polystyrene sheets and put weed mat over the top. This forms a well-insulated, easy-to- clean base. The plants are grown in large containers on top of the base using garden soil and compost. Another bonus is that the plants can be moved in or out of the greenhouse according to the season and their stage of growth. This maximises the usage of valuable space. For example, crops nearing the end of their days can be moved outside.

I’ve placed insect-proof mesh over the vents to keep out a variety of bugs, including such nasties as aphids, tomato psyllid, shield beetles, whitefly and caterpillars. I’m excited about being insect free – I know, it’s weird what excites gardeners – as this means healthier plants, better production, less damage to edible parts and, best of all, no need to spray. Now I just have to work out how to insect screen the door opening, without it being too much of a hassle to get through. The greenhouse has only been operational for a few weeks, but already I have potatoes sprouting, runner beans climbing, ginger and turmeric plants drying off for overwintering, lemongrass reshooting and a whole bunch of tender crops such as tomatoes, cucumbers, capsicum, zucchini and eggplant germinating. Kumara, chillies and early strawberries will follow.

By the end of winter, when supermarket prices peak, we should be self-sufficient from this little hotspot. Not only will this save money, it also encourages the family to eat a lot healthier, at a time that we really need it to fight off the effects of winter.


Andrew Steens