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Grass #3 of 4
by Dan Clost
by Dan Clost


First serious garden earned 25 cents from the Kemptville Horticultural Society when I was 12. Have been poor in horticulture ever since but rich in spirit.

Went to work writing the Good Earth column (over 500 articles published in newspaper, magazine, website and journal.) and learned that what was printed wasn't what I wanted to say and certainly not what Gentle Reader understood me to say. Subsequently have developed a certain clarity and economy of words.

Day job- nursery and production manager for a large nursery/garden centre
Side job- Garden restoration and renovations, design consultations, remedial pruning.
Night job- garden writer and communicator (overnight success in another 20 years)

Dan gardens in Canadian Zone 5b

July 21, 2002

When do we water the lawn? Never at night because the extended period of dampness provides a perfect environment in which molds and fungi can readily establish themselves. Always at night because we don't want to lose any water to evaporation. Both are valid viewpoints and each has adamant proponents. First though let's remember that the purpose is to top up the soil's reservoir for on-demand access by the plant.

Let's start again by saying that we should water once a week if we have a fairly healthy lawn with good drainage. Water thoroughly and deeply to get the grass roots down as far as we can. Okay, here I go hopping down off of the fence: I prefer to water early in the morning. As far as scientific principles go, there is less chance of evaporation than during the heat of the day. Other than that, timing is not as important as watering properly. Why do I like the morning? The air is still and usually the light is just right for detecting anything out of the ordinary. Also, many flowers are still closed providing an opportunity for an undistracted observation of their foliage. It's also a nice quiet time of the day to be outside.

On to mowing. This seems to be the most onerous gardening task judging from comments directed my way. So why do many people cut their grass so short? Do they like weeding, extra chemical intervention, extra watering, weaker roots, longer dormant periods during the dog days of summer, increased susceptibility to disease and pest invasion, and more winterkill? I guess you've figured out where I'm going with this. Let it grow to 2- 1/2". Without measuring it, this is the height where you can see it just starting to wave in a light breeze. If you have a larger lawn, or an estate type sward, let it grow to 3". We know that the green in a plant is due to chlorophyll, the chemical substance that allows the plant to convert light energy into food energy or photosynthate. That little bitty blade we keep cutting off is responsible for feeding the whole plant. For fun, if you're that sort, carefully dig up a grass plant and see how much crown and root there actually is. Did you know that when you cut the plant, a signal is sent to repair and re-grow the missing bit as fast as possible? The grass actually "grows" faster and it depletes stored food. The shorter the blade, the less sunlight is deflected, the warmer the soil, the less blade available to collect dew during the evening.

Here's another reason, passed on to me by Bill Oliphant. Remember awhile back I mentioned we'd talk about bent grass? In our residential lawns it can be considered a weed. When grass is cut short there can be some bare soil exposed. The sun can now activate the weed-seed bank: bent grass is in that mix. It is a warm season grass and doesn't usually grow here because our cool season types, such as blue grass, fescues, ryes etc. get a head start and shade it out. Why is this so bad? First, it hits you in the pocket book. Bent grass uses 50% more nitrogen. Secondly, it really looks bad after mowing. Why? Glad I asked. Glad Bill told me. Bent grass reproduces by stolons, which are stems that run along the surface of the ground; strawberries have them. When you cut the blades of grass, the stolons are exposed. They are brown, not green. They don't look nice at all and this defeats the purpose of the whole exercise.

So, let your grass grow a wee bit longer than you are accustomed. Stick it out for the whole season. Guaranteed: less water used, less time spent mowing, better winter survival. Next week: sharpness and direction.



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