A plan for all seasons | Winter in a Danish garden

Sitting here writing on a gloriously sunny and crisp September morning, it seems somewhat premature to be thinking of the garden in its winter season. But as we all know, the cold weather can jump out and surprise gardeners earlier than expected, so it as well to be ready.

Much of the winter’s work needs to be completed before the frosts really set in – once the soil freezes like iron, there is nothing to be done. And most of the work revolves around getting the garden ready for its winter sleep and preparing for next year.

Beds & Borders – If you have plants in the beds that will not survive a winter outdoors, for example dahlias or gladioli, once the first frost has come, dig them up, wash and dry them, and store away for the winter. A method I have found to work well is to layer them amongst wood flakes – the kind you can buy to put in the bottom of a pet cage – and store them in a big black plastic box with a clip-on lid (easily available at the likes of Sylvan).

Give all beds and borders a good weed – there is nothing more depressing in the spring, once the snow has gone, to look out on weeds!  And so long as the soil remains dry enough, there is still time to dig over any borders and incorporate a whole heap of well-rotted manure (the best stuff I have found is C-Muld from Lyng Naturgodning, www.l-n-g.dk). Don’t be too eager and break the soil down, for it is best left in big clods, for when the frost comes, the water expands into ice, and helps break down the soil naturally – anything to save a bit of work!

Greenhouse – Give the greenhouse, plus any cold frames etc that are empty, a good clean. Disinfecting the surfaces and structure with a solution of Udendørs Rodalon will minimise the risk of pests hibernating and surviving the winter and will help clear out fungus spores – but don’t get the solution on any plants, and give the whole structure a good wash-off afterwards.

Clean glass maximises the amount of winter light getting into the house, so clean inside and out. If you can afford one(!), check your greenhouse heating system is working and the thermostat is set correctly. You can help to minimise your heating bill by lagging the inside of the greenhouse with bubblewrap – I recommend the big bubble type, but don’t forget to ventilate during the day as this procedure can increase humidity levels considerably. 

Lawn – Before the frosts arrive, give the lawn a last trim, but set the lawnmower blades quite high, at about 5 cm. This length of cut makes the lawn look tidy and gives the surface a bit of protection against wear and tear over the winter period. If you have not applied any weedkillers during the past six weeks, compost the cuttings.

Keep raking up fallen leaves as they fall. Why? Because fallen leaves are worm food, and if they’re left, they will encourage worm casts, which can make a mess of the lawn surface. Also, fallen leaves will cause the grass beneath to yellow, and this leads to disease problems.

‘Scarify’ to remove all the dead grass that accumulates at ground level: the ‘thatch’. Left unchecked, a thick layer of thatch will be detrimental to grass growth and harm the natural soil organisms that feed on thatch. The easiest way to scarify is to use a springbok rake and to drag it across the lawn quite firmly, and then again across – don’t panic if lots of material comes out.

Aerating the soil below the turf will improve drainage and encourage healthy grass growth. Simply spike the lawn with a fork, inserting the fork vertically to a depth of 10-15 cm and gently levering back. Work by walking backwards in rows, with 20-30 cm between the ‘inserts’ and the same distance between the rows.

The last lawn job is to give it a feed. At this time of year, I prefer to use granular pellets because they stay around at soil level for longer than a liquid fertiliser, which will get washed through the soil by the autumn rains. Use a fertiliser with a high nitrogen content, so the grass can get a last burst of growth.

Patios, Paths & Deck – The wet conditions can make stone/concrete/brick  paths and patios and wooden decks slippery, as green mould can start to grow over them. My advice, therefore, is to get out there and give the surfaces a good scrub down now. You can use Udendørs Rodalon, but avoid getting it on any plants. Alternatively you can use a pressure washer, but be careful you don’t damage the wood or blast out the sand between the blocks/slabs that help keep the whole structure in situ.

Tools – Don’t be lazy! Give all your tools a good clean to get all the muck off them. Stainless steel tools should then just be wiped dry with a soft rag, but all iron tools should be given a light coating of oil to prevent rusting.

Think ahead and get your power tools serviced now (blades sharpened, engines serviced etc), but have a read of the user manuals to check if you are supposed to leave the petrol tanks dry, batteries disconnected etc.

Lastly – Two last thoughts. It’s time to start feeding the birds that are foolish enough to winter over here rather that following all those sensible swallows south to Africa. And when it does freeze, remember to put water out for our feathered friends too. But at the risk of pointing out the obvious, make sure the food and water is safe from cats. Lastly, come the gloomy winter season, we all like to buy cheerful pot plants for the house and Christmas. Just remember to avoid buying any that are on a stand in the street − they will have been exposed to extremely low temperatures and will probably die in a matter of weeks. And for the same reason, when you buy plants that have been indoors, protect them from the cold on the journey home. The number of times I have seen a hypothermic Poinsettia sitting in a bike basket …!

Toby Musgrave is one of Britain’s most celebrated gardeners – both as an author, historian and design consultant – but yet he has lived in Denmark this past decade, so who better to turn to, to find out everything you need to know about preparing for and enjoying the different seasons. Find out more at www.tobymusgrave.com.

For four weeks at a time, four times a year, our aim is to give you all the seasonal lifestyle advice you need to thrive in the areas of gardening, health, food and sport. When should you plant your petunias, when does the birch pollen season normally start, which week do the home-grown strawberries take over the supermarket, and which outdoor sports can you play in the snow? All the answers are here in ‘A plan for all seasons’.