How to best prepare the lawn for winter?

[omenatalo]

So they say the cold weather is coming and that it might even snow this week in Espoo. Today is fine though and I am thinking there is a chance to mow the lawn one more time before winter. But what do you Finns say? For the health of the grass, is it better to leave the lawn long or short over the winter months when it's buried under snow? I am also keen to do something about all the moss. Do you have any local advice to share on the best treatments and when to apply them? Is that something that should be done before the snow comes or is it best left for the Spring?

A perfect lawn is very important to an Englishman like me, so any advice you can share will be most welcome.

[Rautu]

Basically it is not needed anything for the lawn to get it surviving over winter. If there is a lot leaves, then you can cut them with mower to small pieces, since below tight matt of leaves the grass can die without oxygen. The moss is caused by shadow or acid soil. To avoid moss the trees round the lawn may need to be removed. On the spring it is possible to add calsium (milled lime? I don't know English word for this). Even calsium do not help if there is a lot of shadow. In England the weather is must better for lawn, since there is much more and regularly rainy days during summer. The golf courses in Finland take care of the lawn condition by keeping the grass short and watering it continuously.

[gretheline]

I was born in Sweden but I, too, love a beautiful lush green lawn. I would like my grass to really be greener. And thicker. And oh-so-soft underfoot. Unfortunately my lawn is still far from it, it has moss and bare spots and weeds. I bought this house in March and this summer wasn't the time to tend to the lawn, because we need to grade the slope around the house first and that requires quite a lot of digging before I can start turning my yard into a lush beautiful garden haven.

In order to grow the dream lawn you need to change the conditions, just removing the moss once won't do. If you only remove it, it will grow back. Moss is usually a product of shade, low pH, bare spots, moisture and drainage problems. Other factors are low nutrient levels, low plant vigour, too much moisture, over acidic soils (with low pH), the soil is compacted and lacks organic matter, and grass may be cut too short.
First step in fixing it is dutyful raking with a hard rake. Fertilize your lawn, lawns need adequate fertilization (especially nitrogen), follow the instructions in the fertilizer package of your choise. Usually in shady areas you will need 10-20 grams of actual nitrogen per square meter per season. Also try improving air flow and/or drainage in the area. Then make sure your lawn gets enough sunlight, trim nearby tree branches if necessary. Adjust soil pH. Select a proper grass seed for the particular conditions that you have in that part of your garden and once you have removed the moss and adjusted the pH seed the bare spots with that carefully selected seed. Avoid excessive watering, water based on lawn needs only.

Someone also recommended a product called "lawn sand" for moss removal, I don't know if you can get it ready-made from garden supply stores here in Finland, but I found DIY instructions online:

• Lawn sand is a mix of one part sulphate of iron, three parts sulphate of ammonia and twenty parts of dry sand. It is applied at the rate of 140 grams per square metre. The sand material acts as a carrier for the active ingredients (iron & ammonia). It is important when using these materials to ensure that they are spread evenly over the turf surface. The best method of spreading lawn sand is by using a spreader."

The very same article said that

• ...baking soda can also be used. Baking soda will not affect your lawn or surrounding plants but it will kill the moss within a week. Simply sprinkle a container of baking soda over the moss. If necessary, mix it with some vinegar and water and apply with a spray bottle.

About mowing your lawn, never cut more than a third of the grass' height at a time. If you want it shorter, wait for a few days and cut another 1/3. Short mowing may be a source of a moss problem, and to keep the moss at bay 6½ to 9 cm is the recommended length.

Fertilizing is usually done in spring, but of course you can start now with all the other improvements in the conditions of your lawn. Personally I will just rake the leaves this year, and dream about my dream garden while raking. I hope that sme time next year some parts of that dream have already come true.

[omenatalo]

Thanks so much for the expert advice.

This is the first year I have been able to pay attention to our garden since moving to Finland five years ago. Thanks to the wetter summer this year and a bit of work my garden has finally started to show its potential so I'm hoping to set everything up for an even better showing next year.

Shade could be the main cause of moss in our lawn. I have several apple trees and our lawn is also shadowed by the neighbour's tall pines and birch. The moss is a lot worse in the shady areas. I think you are right about mowing height. I raised the height of my mower this year and it seems to have helped a lot. I gave fertilizer to a few trouble spots and they responded really well so it could be that the whole lawn needs fertilising next year. I think the drainage is OK as our land slopes away from the house on all sides.

Lawn sand sounds like a promising solution but I would have no idea where to buy those ingredients! Maybe I'll try the baking soda first.