With sub-zero temperatures upon us, the RSPB is advising people to make sure their bird feeders and tables are full of high-energy foods - plus, find out what else needs doing in the garden this week.
By Hannah Stephenson
How long is it since you filled your bird feeder or replenished the water in your birdbath? If you haven't done it for a while, there's no time like the present.
"The sudden drop in temperatures across the UK will have been a big shock to birds' systems after spending the past couple of months with few worries in terms of food availability," says Richard James, RSPB wildlife adviser.
"Thanks to the recent mild weather, many natural food sources have been readily available and water has been easy to come by. Now the snow and ice are here birds will need all the help they can get to survive the winter."
However, the range of bird seeds, fat balls and other so-called bird-friendly items can leave gardeners baffled as to what's best for our feathered friends.
The RSPB suggests calorie-rich foods such as mixed seed, nyjer seed, fatballs, suet sprinkles, sunflower seed and good quality peanuts, as well as kitchen scraps such as mild grated cheese, rice and porridge oats.
There are different mixes for feeders and for bird tables and ground feeding. The better mixtures contain plenty of flaked maize, sunflower seeds, and peanut granules.
Small seeds, such as millet, attract mostly house sparrows, dunnocks, finches, reed buntings and collared doves, while flaked maize is taken readily by blackbirds.
Tits and greenfinches favour peanuts and sunflower seeds. Mixes that contain chunks or whole nuts are suitable for winter feeding only.
Pinhead oatmeal is excellent for many birds. Wheat and barley grains are often included in seed mixtures, but they are really only suitable for pigeons, doves and pheasants, which feed on the ground and rapidly increase in numbers, frequently deterring the smaller species.
Avoid seed mixtures that have split peas, beans, dried rice or lentils as again only the large species can eat them dry. These are added to some cheaper seed mixes to bulk them up. Any mixture containing green or pink lumps should also be avoided as these are dog biscuit, which can only be eaten when soaked.
Don't feed the birds cooked fat from roasting tins and dishes, because the fat may have blended with meat juices which leaves a mixture prone to smearing, which is not good for the birds' feathers, and is a breeding ground for bacteria, the charity warns.
Polyunsaturated margarines and vegetable oils are also unsuitable as birds need high levels of saturated fat to retain the high energy to keep warm, and soft fats can be smeared on to feathers, destroying the waterproofing qualities.
Lard and beef suet on their own are fine as they re-solidify after warming and are not as prone to bacteria breeding because they are pure fat.
Never give milk to the birds because it can result in serious stomach upsets or even death. They can, however, digest fermented dairy products such as mild grated cheese, which may attract robins, wrens and dunnocks.
If you want to give the birds coconut, only give them the fresh stuff in the shell, rinsing out any sweet coconut water before hanging it out, to stop black mildew emerging. Desiccated coconut should never be used as it can swell inside the bird, with fatal consequences.
Cooked rice without added salt can be beneficial to birds during severe winter weather, while uncooked porridge oats are fine for many bird species. You can also put out small quantities of dry breakfast cereal .
A supply of water is also essential for bathing and preening. In freezing conditions birds become more dependent on water provided in gardens, since many natural sources are frozen over.
The most effective way to keep the water in your garden from freezing is to pop in a light ball that will be moved by even a gentle breeze - a ping-pong ball is ideal.
Alternatively, pour on hot water to melt the ice to make sure the birds can get to it.
Put out enough food and you may see a wider variety of visitors during the RSPB's Big Garden Birdwatch (Jan 26 and 27), the world's biggest wildlife survey.
:: For more information, visit www.rspb.org.uk Best of the bunch - Corkscrew Hazel (Corylus avellana 'Contorta') Its curiously twisted branches look particularly striking against a backdrop of a clear blue sky and it provides a conspicuous, if a little spooky, edge to the winter scene.
While many hazels are too big to grow in the average garden, the corkscrew hazel is slow-growing, so will take years to reach its eventual height of 5m.
In February the stems will be further decorated by the 5cm (2in) long pale yellow hazel catkins. It is ideal underplanted with early flowering bulbs and marble-leaved arums and will grow in sunny or semi-shaded sites in fertile, well-drained soil. Remove suckers and any unwanted stems in the winter.
Good enough to eat - Garlic We have garlic in so many dishes these days that it's not difficult to justify the little time and effort it takes to grow your own.
Buy bulbs that are certified virus-free from seed merchants rather than planting one you've bought from a supermarket because the results may be disappointing if you cut corners.
Break up the bulb and plant the cloves in prepared, well-drained ground in a sunny spot, placing them 15cm apart and pointed end up, so the tip is just covered with soil.
Cover them with cloches in frosty weather. Each one will produce a whole bulb which should store until the following spring.
If you live in a cold area, speed up the process by planting the cloves in divided seed trays in multi-purpose compost, water in well and place them in a cold frame or unheated greenhouse.
They should be ready for planting out in March or April. In dry spells, keep garlic well watered or you may find the resulting bulbs don't keep for very long.
Three ways to... Save plants in windy gardens 1. Avoid plants with big leaves and those that come into flower early in the season because they are more vulnerable to wind damage.
2. Protect vegetable plots with windbreak netting, as wind will slow plant growth by increasing water loss through evaporation, and keep new plants well watered.
3. Try to grow fruit crops against sheltered walls because pollinating insects avoid windy areas.
What to do this week :: Protect winter-flowering bulbous irises in the garden from severe cold or damp.
:: Brush snow off the branches off shrubs to avoid the branches snapping under the weight.
:: Start forcing pots of lily bulbs for Easter and early summer flowering.
:: Give perennial vegetables such as asparagus and artichoke a dressing of general fertiliser, which will have time to wash down to their roots, ready for the new growing season.
:: Sow an early crop of salad onions, such as 'White Lisbon', in a greenhouse border.
:: Apply a winter wash over your fruit trees and bushes to stop overwintering pests in their tracks.
:: Continue to plant bare-root trees while they are dormant, if weather permits and the ground is soft enough.
:: Renew compost in permanent pots by scraping off the top couple of inches and replacing it with fresh compost.
:: Move containers to a sheltered spot during freezing weather.
:: Trim down agapanthus stalks and wilted leaves at the base while they are dormant.
:: If any of your variegated shrubs show plain green shoots, cut them off a the base or they will quickly outgrow the variegated leaves.