Monthly Archives: December 2010
The cold, cloudless evenings in the , winter could be hazardous to the health of your plants and flowers! Protect your Plants from Frost During the day, your plants and the soil absorb and store heat from the sun. As the day turns into night, your plants quickly begin to lose all of their stored heat. Clouds will help to insulate and slow the loss of the heat, but a cloudless, wind free night will afford no protection whatsoever. The temperature within the soil and in the plant’s cells may even drop to a few degrees colder than the air. As the temperature drops, the moisture in the air condenses into dew, which then freezes when the temperature reaches 32° F. on the plant surfaces. At 32°, damage to most plants may be minimal, and only affect a leaf or two. However, if the temperature drops far enough for the plant cells to freeze, non hardy plants will die. Weather conditions can bring about a frost, even in supposedly frost free areas. It is important to heed the warning when your local forecaster announces frost, and take precautions to protect your garden. Often it is possible to extend your growing season by several weeks if you are able to keep your plants alive through a single early frost! The best way to avoid frost damage to your plants is to grow plants that can withstand the frost. The term ‘frost hardy’ is often misleading because of the degrees of frost (i.e. light frost vs. hard killing frost). It is a good idea to ask a qualified local nurseryman what is suitable to grow in your area. Even better, look around your own neighborhood, and see what survives and thrives in other local gardens. Often a plant will survive frost on the foliage, but the same frost would kill any flower buds which have emerged so in areas where late spring frosts may occur, you should choose varieties of plants that bloom later.. Cold air, being denser than warm air sinks, so low lying areas of your garden can be several degrees colder than other, higher spots. Consequently frost may occur in these areas when there is no frost evident anywhere else in the garden. Plant your more tender plant species on higher ground or on slopes where the cold air will flow past the plants as it moves to the low point. Any sloping area is far less prone to frost, because the cold air can’t settle there as easily. Precondition your plants to withstand cold temperatures by discontinuing fertilizing in early September, so that no new foliage is on the plant when the cold temperatures arrive. Older leaves are much tougher and more capable of surviving a frost. More Tips to minimise the freeze! Place a plastic ball to float in ponds to help prevent ice forming and to ease making an air hole for fish to receive oxygen. Top up stocks of fuel for greenhouse heaters and insulate greenhouses and frames with bubble polythene. Further protection can be given by laying fleece over plants in greenhouses or frames and covering frames with old carpets at night or during severe cold snaps. Move tender plants in pots to a sheltered place. Greenhouses and conservatories are ideal, especially if they can be kept frost-free. Otherwise wrap the pots in bubble wrap or bin liners filled with straw, cardboard or leaves, and place the pots against a sheltered wall or an open-fronted shed. Garages and other buildings are often too dark, but can be successful with care and luck. Go easy on watering containers – plants with dryish roots are better placed to resist cold than ones in soggy compost. Mulch the root zone of evergreens, conifers, tender shrubs and tender perennials with coarse organic matter to help exclude frost and prevent the ground being frozen. Keep a long pole handy to shake snow off hedges and trees to prevent the snow’s weight causing breakages. Avoid pruning in freezing weather. Bonfires can be fun, but do be considerate to your neighbours and don’t break local bylaws. Wrap tender foliage in fleece. Be aware that fleece only gives a degree or two of protection so consider straw packing inside the fleece to limit frost damage. Drain watering equipment, sprayers and external plumbing. Don’t allow liquid fertilisers and pesticides to freeze as this often ruins them. Avoid letting lifted dahlias, cannas, gladioli, stored vegetables and fruits freeze. Keep a stock of parsnips, leeks and other vegetables in a frost-proof place in case frozen soil prevents harvesting. If you have digging to do, cover the area to be dug with cardboard, old curtains or old carpet to keep it workable. On a positive note, frozen ground can be helpful if you need to barrow materials such as compost around the garden – just avoid treading on frozen grass as your footmarks will be visible for weeks.