With such an early start to spring, I'm about a month ahead in the garden. Brassica and silver beet seedlings are planted out, young spinach is up, the Chinese greens are strong, and the radishes are growing at a rate of knots. It should all look wonderful – it's just that I can't see any of it! That's because my entire garden is covered in plastic. In fact, if I look around at the makeshift cloches and plastic bottles (bases cut off) dotting the raised beds, the place looks like nothing more than a giant rubbish tip. Yes, it is warm enough for the plants to be in the ground uncovered but, my goodness, the growth is certainly accelerated when the warmth is trapped under a layer of plastic.
I use plastic from day one, laying it over beds prior to sowing seed so that the ground is encouraged to warm up. When I'm ready to sow, I make 5-6 cm deep furrows for the seed drills so that the ridges on either side act as props for the plastic sheeting I then lay on top. As the warmed moistures rises from the ground, it condenses on the plastic and drips back onto the germinating seeds. Under this sheet of plastic, germination takes place in a fraction of the time it normally would at this time of year. Developing seedlings will happily grow two or three centimetres high before I need to elevate the plastic with hoops of plastic pipe to form low cloches. Unchecked by wind or cold, the growth of these plants is exponential, and everything is lush and tender. By the time late spring comes around, we'll be eating our spinach and lettuces, and sowing out the next batch.
What I like best about plastic in this early part of the season is that it can also be used to cover climbing plants such as peas (green, sugarsnap, and snow) and runner beans, allowing them an earlier than usual start to the season. The secret is to grow these climbers up a tee-pee of poles pressed into the ground and tied or wired together at the top. (Lengths of bamboo, willow wands, or flax-caddies all make good poles). Sow seeds on the inside of the tee-pee, then wrap a large sheet of plastic around the outside of the construction, securing it at the base with bricks or stones, and holding it together down the side with strong clothes pegs. A natural gap at the top will allow for ventilation, especially necessary on warmer days when you do not want your plants to 'cook'. This pitched mini greenhouse provides a warm, moist environment and can be left on right up until the time the plants are flowering, at which stage you can open your tee-pee to allow pollinating insects to visit. Don't be in a hurry to remove the plastic from the tee-pee. Instead, simply roll it down to the ground so that if cool or windy weather arrives unexpectedly, you can pull it up over the plants again.
My spring garden may not be much to look at, but under all that plastic, my plants couldn't be happier – and neither could I.