November 30, 2010 0 comments

Insulating your Greenhouse – Winter Tasks

This is the month when temperatures dip so you need to protect cold frames and cloches with insulation, winter crops like lambs lettuce are certainly hardy enough to survive but added protection will certainly increase their quality. Open the vents in your greenhouse as long as possible on mild sunny days, shutting them down before temperatures drop early in the afternoon to capture the heat. A combination of high temperatures and low light makes leaves and stems soft, spindly and prone to grey mould which spreads rapidly in cool, damp conditions. Good air circulation is essential but chilling draughts should be avoided, so don’t leave the door open and err on the side of caution!

It is a good time to check over your gardening tools, replacing broken handles and sharpening blades. Brush away any soil, clean off rust with wire wool, spray the surface with water repellent and treat wooden handles with linseed oil before hanging them in the shed and use a fine file to flatten notches on the cutting edge of hoes and spades Whatever you choose to sharpen blades, don’t check the edge with your finger; try cutting a branch or twig instead, for obvious reasons.

Chilli plants can be overwintered on a sunny, south facing windowsill where temperatures are slightly higher than in the greenhouse and will continue to hold their bright red fruits through the winter. If you have plants that were harvested in autumn can be cut back within a few centimetres of the main stem and stored over winter. This year I bought a couple of ‘end of season’ plants from a garden centre for £3, it’s a great time to buy them if you have space to keep them over winter, you will not only have a bargain but earlier crops next year.

Light soils are vulnerable to winter rains washing through them and removing the nutrients, particularly nitrogen. If you haven’t sowed green manures, like winter tares, which take up take up the nutrients so they can be dug in and released again next year, you can still protect the soil by covering the surface with a layer of well rotted organic matter, this can be dug in next year before the seedbed is prepared. If you don’t have access to organic matter, let the weeds grow and dig them in spring well before the perennials mature, they will release the nutrients stored in the stems in exactly the same way as well rotted organic matter.

Cold, frosty weather can freeze root crops like parsnips and maincrop carrots in the ground, so they can’t be lifted when needed. To prevent any problems, either cover them with a thick layer of straw or bracken or lift the roots and store them on boxes of damp sand ready for use.

Harvest sprouts from plants by picking them from the bottom upwards, which helps the smaller immature sprouts near the top to develop, removing any ‘blown’ sprouts or yellow leaves; the leaves at the top can be harvested and steamed or lightly boiled, too. Finally, don’t forget to enjoy the fruits of your labour in your Christmas dinner.

Happy, Holly filled  Christmas to you all!

Matt.

Matthew Biggs  

About Matthew Biggs

He is a regular panellist on BBC Radio 4’s ‘Gardeners’ Question Time and author of several gardening books, including Matthew Biggs’ Complete Book of Vegetables, Gardening at Eden and How to do it at Home about the Eden Project and has contributed to two Gardeners’ Question Time Publications, their Plant Chooser and Techniques and Tips for Gardeners. He appears regularly on QVC with his own programme ‘Matthew Biggs’ Gardening Solutions, co-hosted Channel 4’s Garden Club for five years and Directed ‘Grass Roots’ for Meridian Television. He writes regularly for several magazines, including ‘BBC Gardeners’ World’ magazine, ‘Gardens Illustrated’ and the Royal Horticultural Society’s Magazine, ‘The Garden’. He is Course Director of the Plants and Plantsmanship Course at the English Gardening School and leads plant and gardening cruises, worldwide. Matthew is a graduate in Horticulture from the Royal Botanic Gardens, Kew.

Why a Hartley? Hartley Botanic