Winter jobs: sow seeds that need the cold to germinate

This is the last chance you will get to sow seeds that need a period of frost in order to germinate. Many of our native trees and shrubs – oak, beech, blackthorn, hawthorn, spindle – and other plants, such as alpines, that come from chilly places, use a period of cold as a way of timing germination.

By requiring a lengthy chill before they germinate they ensure that their seeds don’t start their vulnerable young life during a mild spell in winter, only to find themselves facing the toughest conditions of the year. Some, such as ash, even have multiple dormancy needs: cold, then warmth, then cold, then germinating in the spring after the second winter.

You can fake single or multiple dormancy at any time of year by popping seeds into a bag of moist compost and then into the fridge, but if you prefer a simple life now is the time to do it. Growing trees and shrubs from seed is no quick fix however, and it will take a good number of years before they are of plantable size, but it is a cheap way to get hold of many specimens for a new garden.

Prepare pots filled with a mix of half compost, half horticultural grit. Water well, and then sprinkle small seeds across the surface, or push larger seeds just below it. Top with another layer of gritty compost, water and label. You need to site the pots where they are exposed to the cold, so well away from the warmth of the house, but also where they won’t be disturbed or knocked over. A cold frame is ideal.

Hopefully small forests will appear across the tops of your pots come spring, and after a few months you can knock them out of the pot and into their own individual ones, ready to grow on.

The Almanac: A Seasonal Guide to 2018 by Lia Leendertz (Unbound, £9.99). To order your copy for £7.99 plus p&p call 0844 871 1514 or visit books.telegraph.co.uk