Monthly Lawn Care Tips

How to mow for best results

Mowing is the most common cultural practice used on lawns around the world. In fact the ability to tolerate mowing is one of the criteria that separate turf grasses from the rest of the grass species. There are many misconceptions about mowing that can lead to a less than perfect lawn and many homeowners are making lawn care difficult by using the wrong mowing practices.

Mowing Basics

Mowing is always a stress on the grass plants. Just because they can tolerate the act of mowing does not mean they like it. Try and reduce the stress on the plant by mowing early in the morning or even better in the evening. Mowing during the heat of the day can cause the plant to go into shock. Mow when the grass is dry. Your mower will work better and there is less likelihood that disease will be spread from plant to plant.

Never mow off more than one third of the leaf in one mowing. If you are mowing your grass at 2 inches don’t let it grow over 3 inches. A drastic decrease in height can shock the plant. This doesn’t mean you can let it grow to 4 inches and mow off 1 inch in the morning and another in the afternoon. The plant will show the signs of this abuse.

Make sure your mower blades are sharp. Dull mower blades will tear the grass instead of cutting it. This often leaves a tan or brown tint to the lawn after mowing. Torn grass blades are more likely to get infected with a fungal disease than nicely cut grass. Check the turf often after mowing to make sure your equipment is in good condition.

Leave your clippings on the lawn. Clippings are full of nutrients and can actually reduce your need for fertilizers. Grass clippings readily breakdown and will only cause an issue if the quantity is excessive. Mulching mowers are great at making the clippings small enough but even standard discharge mowers will not cause a problem if you are following the one third rule.

Mowing often lays the grass over slightly (this is how the patterns develop) and it is important to change the direction of mowing so the grass does not lie over excessively. Changing the pattern can also reduce wear and compaction by changing the areas that are travelled.

Mowing Heights Effect Lawns

It is always best to maintain lawn grasses at the top end of the recommended height range. Leaving the grasses longer has many benefits. Longer grass shades the soil keeping it cooler which will reduce evaporation of water from the soil. This shade also reduces the opportunity for weed seeds to germinate. If grass is mown too short the lawn will be much more susceptible to weed invasion.

Think of the grass blades as solar panels for the plant and the roots are the energy storage cells. Leaving grass blades long increases the size of the solar panels and results in greater energy storage and root growth. Root growth is often directly proportional to leaf growth. The longer the grass blades the deeper the roots, allowing grass to find water and nutrients at greater depths.

It is often thought that if you mow the grass shorter it will allow for a longer duration between mowing. This is untrue. Short mown grass wants to rapidly grow back what it has lost. The grass will pull reserves from the roots to increase shoot growth. This decreases rooting and increases the chance the lawn will show signs of drought or heat stress.

Grass can be neglected to the point that it grows too long. Over a certain height grass will not support its own weight and will begin to fall over. This can cause the underlying grass to be smothered and die. This can also lead to excessive moisture being trapped in the turf canopy increasing breeding of fungal diseases.

First day of spring?

It was the first day of spring yesterday but, with the forecast over the Easter weekend predicting snow, it feels anything but spring-like.  Since my last entry below, lawns have virtually stood still with little or no growth.  Soil temperatures have remaimed low, and the constant east winds have taken their toll on grass clour.

From the calls we are getting, the two main current lawn problems are worms and moss.  The worm problem is a tricky one.  In some cases, worms can completely ruin a lawn.  All the effective worm killers have been taken off the market, probably for quite sound reasons - some of them were quite nasty chemicals.  Professionals, like golf greenkeepers, use a fungicide called carbendazim which seems to deter worms.  This chemical is not availabe for home use.  And anyway, the regular use of fungicides for worm control is not a good idea because many of the beneficial fungi in the lawn are killed at the same time.

One thing that works quite well is to make the soil under your lawn a bit more acidic.  This seems to deter worms from coming to the top and depositing their casts on the surface of the lawn.  How do you make it more acidic? 

Well, iron sulphate, the most effective material for moss control, produces an acidic reation in the soil.  And iron sulphate is the main ingredient in our Maxicrop Liquid Lawn Moss Killer.  So if you are using it to kill the moss in your lawn, you will get the side benefit of discouraging the worms from coming to the surface.  Many people use it for the worm control alone with pretty good results.

As we get towards the end of March it's time to feed the lawn.  The best lawn feed to use is contolled-release fertiliser, or CRF for short.  The new technology in CRFs is fantastic because you don't waste the nutrients in the feed through leaching.  (Leaching means "being washed through the soil after rainfall").  Nutrients like nitrogen and potassium are very soluble in water, and you can soon lose the benefit of standard fertilisers.  However, in CRFs, each nutrient granule is surrounded by a protective polymer coating.  This coating allows the nutrient to seep out over a period of months in a controlled way.  It's like drip-feeding.

This has two important benefits.  First, you don't waste fertiliser nutrients through leaching.  Second, mowing is less of a chore because the grass grows slowly and steadily instead of in fits and bursts.

Clike here to read more about controlled-release fertiliser. 

8th February 2008

First sign of growth

Have you noticed that lawns have got greener in the last two weeks?  This is a sign that soil temperatures have started to move upwards.  Nitrogen is being released into the soil by the mineralisation of organic matter.  In other words, it's warm enough for the soil bugs to get to work.  When the grass starts to grow strongly in March, the nitrogen provided by the mineralisation of soil organic matter is no longer sufficient to support healthy growth - and that's why we need to apply additional nitrogen in the form of lawn feed.

This weekend is set fair.  So it's worth trimming the lawn if it's got a bit straggly over the last few weeks.  But remember not to mow too low!  One of the biggest mistakes lawn owners make is to mow too low.  As a general rule, 25mm (1") is the lowest you should be mowing your lawn.  Any lower and you will be reducing the ability of the grass to keep weeds and moss at bay.

Talking about moss, the wet weather seems to have encouraged it to infest many lawns.  The key to contolling moss is to act early.  By the time it has become thick pads it's much more difficult to eradicate.  Maxicrop Mosskiller and Lawn Tonic is an excellent way to keep on top of moss.

The recent high winds have deposited all sorts of debris on lawns.  Make sure you pick up all the twigs and stones before you start mowing or you'll soon have a blunt blade.  Keeping your mowing blades sharp ensures a nice clean cut, and reduces bruising to the grass leaf.  If you've got lots of worms casts on the surface of the lawn it's worth scattering them with a rake before the first mowing.  If you don't, the mower could smear the casts into small brown patches.