How to care for the spring garden in a cold climate
Gardening in a cold climate really is quite a bit different than in a more tempered climate, and I can say this with certainty after having been a keen gardener both in the UK and Finland. In London the mean average summer temperature is 21 °C/ 70 °F, and average low in winter is 5 °C/ 41 °F. In Finland, the average summer temperature is 17 °C/ 62 °F and during the coldest month - 6 °C/ 22 °F. Finland and Sweden, on the other hand, have fairly similar climates but there one has to consider that Helsinki is actually much further north than Stockholm, and therefore there are a whole host of plants that will happily make it through winter in southern Sweden but most definitely not in Finland. Also, as cold climates are further north this means that they have much more daylight hours during summer. This is an important factor, as the abundance of light makes everything suddenly go "WOOSH" and grow much more furiously than in tempered climates with fewer daylight hours.
Another difference is that the winters in a cold climate are long, snow filled and cold, which means that vegetation dies back in autumn to regrow in spring. There are few evergreen plants, appart from spruce and other conifers, and you can forget about having a "winter garden". Trust me - nothing happens in winter in the garden! The cold limits the varieties of plants available, as many simply will not survive below zero degrees celsius. In my English garden I used to love using box hedging and had masses of butterfly plants such as buddleia, lavender and purple top vervain (Verbena bonariensis) but in my Finnish garden none of these will survive. Instead I have lilacs and spirea, hyssop and peonies and oregano. Its just one of these things, I have had to find new favourite plants to use instead.
The growing season is different too. Here the garden is dead from late October until the first of May. I personally use the first of May as a season marker, because even if the ground is free of snow in April it is really not worth it to clear last seasons leaves and twigs until the May bank holiday weekend. Late spring frosts are the norm, and if the garden is cleared of debris too early the cold may kill of the earliest spring growth. Another reason for leaving debris a little bit longer is to give the insects a chance of waking up and finding food and new lodgings before their winter home is demolished. As you probably know, insects are the organic gardeners best friends and should be encouraged in every way possible to set up home in the garden because they keep pests away. (Technically I guess pests are insects too, but thats another story...)
I tend to clear the flower beds by the time the spring bulbs poke their heads through last years debris. The bulbs do get a bit manhandled by the rake, but mostly they don't seem to mind very much. At the same time, I also cut any branches on the bushes that have broken of under heavy snow, or grow inwards towards the bush. I like to keep my bushes airy, as it seems to prevent disease when they are less crowded and the branches don't cross each other too much. I am a great fan of composting, so the material I gather from the ground is unceremoniously dumped on my enormous compost heap. However, I tend to burn twigs and branches - especially from the fruit orchard - as I am vary of spreading any incubating bacteria or disease. This is also why I wash and disinfect the secateurs after the spring pruning. It doesn't take much time, and it pays off being careful.
Some perennials leave tough, wiry stems that don't fall off easily in spring, and these get some extra attention. Peonies for example will have their flower and leaf stems clogged in a heap, and they take a bit more time to sort out. I actually use both secateurs and a pair of really styrdy scissors to cut off these stems as new buds are forming underneath and they are easily broken by harsh handling. I love peonies, and although these take more time in spring I do find them worthwhile. I guess one could cut them down in autumn as well, but since they can sometimes be sensitive to hard cold I prefer to leave last years growth on to protect them over winter. There are in fact a lot of my favourite perennials that need this kind of care, where last years growth is cut back by hand in spring. Ladies mantle (Alchemilla mollis), Daylily (Hemerocallis) and Lamb's ear (Stachys byzantina) to name a few.
Once the soil is visible, I check for weeds and then mulch with anything from compost to bark and wood clippings around the perennials and bushes. In areas that are used as paths I always use old cotton or linen fabric (sheets, table cloths, towels) underneath, as it takes a few years to compost and keeps the weeds at bay by providing an un-penetrable cover. I dislike using plastic membrane, as I am suspicious it will leave residue in the soil and in the end needs to be removed at some point as it takes far too many years to really disintegrate into nature. (Does plastic even disintegrate..? I fear not at least in my lifetime.)
May is therefore a very busy month! I love my free flowing flower beds, but they do demand a lot of attention. If left to their own devices, they would be filled with weeds by mid June! The moment before everything starts growing the garden looks orderly and bare, but this is the ultimate deception! Give it a few weeks, and suddenly the world springs to life and greenery takes over. This is perhaps the biggest difference in my mind between having a garden in a tempered climate and a cold one - in the UK spring started slowly somewhere between February and March, and continued into April before slowly turning into summer in May. In Finland on the other hand, first there is nothing but cold snow and ice for the longest time, and then suddenly in May it is spring and before you know it it is June and full summer! So as a timeline, I try to put the garden in order between the time the first daffodil bulbs appear and be ready with the cleaning and mulching by the time they bloom. Happy Easter friends!