Lawn Care Tips in Spring
Lawn Care Tasks in March
How to cut the grass
This is the month when the grass starts growing strongly and needs regular mowing. Now you might ask why you should be told how to cut grass. Well, it’s not just as simple as lowering the height with each successive cut, although of course that’s a part of it. Grass needs mowing a little at a time and, depending on the type of grass and its different uses, at different frequencies.
The aim is to remove a third of the available leaf each time you mow, allowing the grass time to recover from the cut. Leaving the majority of the leaf intact allows photosynthesis to turn compounds such as water into food for growth.
Take off two thirds or more and you’re exposing the grass plant to disease attack as it becomes weaker, thinner and showing yellow in colour. You also need to consider the type of grass being cut, the cut height and frequency of mowing. Ornamental grass in summer should have a cut height of 5 – 10mm and be mowed every two or three days. Leisure grass 15 – 20mm summer cut every three of four days and utility grass 25mm every six or seven days. Remember, these are yardsticks and not hard and fast rules because it depends on weather conditions and the extent of the growth.
Mowing when the surface is dry will be easier and prevents the mower blocking, unless you’re using a garden tractor that’s designed to cut in the wet as well as the dry. So, over the next three months reduce the cutting height slowly until you reach the desired height for the summer cutting, then as winter approaches you start raising the height again.
Other lawn tips for March are to ‘over-seed’ by raking with a tine rake and applying seed for new growth. On a large lawn lightly scarify with a walk-behind scarifier or one that attaches to your garden tractor and then apply the seed. Watch out for disease and weeds and treat where needed.
Lawn Care Tasks in April
Feed me, feed me
Grass is a plant the same as other plants and requires periodic feeding. In the long term, it will be beneficial in a number of ways, including colour and appearance, disease resistance, density and wear tolerance. But before we race out with a bag of fertiliser we need to identify our grass. Fine-leaved fescues need very little complete fertiliser, usually once a year is enough.
A lawn with a high percentage of rye grass–Lolium, or bent grass–Agrostis, needs more frequent application. For most of us, our lawns need just one application of a complete fertiliser containing the main foods the grass needs. These are nitrogen (N), phosphorus (P) and potassium (K). However, a lawn that has to endure high levels of wear through the year may require more frequent applications of fertiliser, say, in spring then autumn.
Soil type is another consideration, with grass on very sandy soil needing two to four light applications a year. For clay loam, silt loam and organic, it’s one or two light applications. In spring, once the grass is becoming active, it is the time to apply fertiliser but not too early in the spring as that can encourage disease.
For the lawn with a lot of moss and thatch, you may choose a 4-in-one fertiliser, weed and moss killer such as Evergreen 4-in-one. Once the treatment becomes effective, you will need to rake out moss and thatch or scarify with the cassette on the garden tractor or mower or use a walk-behind scarifier/aerator. This is likely to leave bare patches which will need seeding with a good grass seed and overseeding for larger areas.
With mowing throughout the season, the grass has little chance of laying its own seed, so it periodically needs this helping hand. Consider as well the possible causes of moss and a build-up of thatch. Drainage and getting air to the grass roots can be managed with aeration. Overhanging trees or bushes create shade and encourage moss so if you can, cut back branches to let the light in.
Remember, don’t use a fertiliser with high levels of nitrogen and water after treatment if there is no rain. The other rule of thumb is the higher the height of cut, the healthier the grass will be. So, lower your cutting height gradually as you progress through the season.
Lawn Care Tasks in May
Why my grass seed will not grow
Having scarified and aerated a back lawn, it was time to deal with bare patches and overseed. While grass seed germinates in most conditions the weather does need to be right. Soil temperature needs to be between 9 to 12 degrees Celsius.
Usually from March through until September is the best time to sow seed. Moisture is also needed, and we had plenty of that in March and April. But two sowings of fast-growing seed, once in March and again in April produced little or no result.
The conclusion is the climate and soil has been too cold in our area. A ground thermometer test supported this theory because all other rules had been followed as usual. So we are waiting for much warmer weather before overseeding again and then it’s likely to be dry, so watering will be necessary.
Other problems with the lawn at this time of the year will show up this month. Prolonged or heavy rainfall will have pointed to areas of standing water, where the ground may be compacted. Aeration and spiking will help with drainage and get air to the roots.
Moss can be a problem in wet and shady areas of the lawn. Because moss reproduces by releasing thousands of spores, it needs to be dead before removing it. Ferrous sulphate in lawn sand kills it efficiently while the ammoniacal nitrogen helps to stimulate the growth of the grass plant. You simply water in the lawn sand and rake out the moss once it is blackened and dead. Any bare patches that are left can be seeded and (hopefully) will quickly germinate with the warmer spring weather.
Weeds can be persistent this month as well so if you didn’t do a ‘weed and feed’ application in April it may be necessary to give the lawn an application of a selective weedkiller which can be done with a powered spreader or walk-behind pedestrian type. Those of you lucky enough to have a lawn growing lush, weed and moss free, will be lowering the deck on the garden tractor or adjusting the cutting height on the mower from now on.
