January is usually the coldest month with hard frosts although there are no guarantees with our weather.
General Garden
Prepare potato tubers by planting them in egg boxes to encourage eye growth.
Prune rose trees as they are still dormant.
Vegetable Planters
Some vegetables will grow in the winter. Make a compost trench using old stems once cropping has finished.
Garlic and shallots can be planted until March.
Fruit Cage
Resist the temptation to prune fruit trees with the exception of apples and pears etc as they’re dormant. Don’t prune any stone fruits until May (apricots, cherries, plums etc) when risk of silver leaf infection has past.
Bare rooted trees and bushes can still be planted until March but rotate spots around to avoid “specific replant disease”
Growing in the Greenhouse
Sow seeds for hardy vegetables like lettuce, spinach, turnips, cauliflowers, broad beans, onions, radish, peas, aubergines and cabbages. Chives, Basil and parsley also. Germination will occur around 13 degrees C (55.4F)
Tomatoes and aubergines can be sown. They will do best in a heated propagator to get them going.
Onions from seed can be sown in January but unlike tomatoes who like it hot, you want the temperature around or slightly below 15C for onions.
Try growing 2 or 3 potato seed tubers in a bag of compost in the greenhouse. See growing potatoes in bags in the greenhouse A lot depends on your location, I’d leave it until mid-February at least here and early March in the colder areas of the north.
Flowers such as Pelargoniums, sweet peas, dahlias, delphinium, begonies, cornflowers, petunias and “IF” it is fairly mild even Chillie plants (though best in the house).
Harvest
Parsnips and swedes in the ground can come up when you are ready, cover with fleece or straw to stop them freezing solid into the ground. You may even have some winter radish.
Winter cabbage at least should be available and Brussels Sprouts which may well go through to March.
Prune gooseberries, blackcurrants and redcurrants, cutting sideshoots back to three buds from their base.
Summary
Jan – Mar | Blackcurrants – prune |
Jan – Mar | Gooseberries – prune |
January | Save inner cardboard tubes from toilet rolls for runner beans etc |
Week 2 | Shallot – plant sets in 8cm pots in protected position |
Week 3 | Buy or borrow a soil testing kit (Brussels sprouts etc.) |
Week 3 | Add lime if necessary to reduce soil acidity (Brussels sprouts etc) |