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Lawn Care - Weeds


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Overview:

There are a number of troublesome lawn weeds, some of which can be difficult to control.

For example; Yarrow, Field woodrush, and the many species of Speedwell.


Yarrow:

A clump of 'ferny'weeds

Yarrow

This is a difficult weed to control, and thrives where grass has been weakened by drought and lack of plant nutrients.

It has some resistance to the few weed killers available to the amateur gardener.

Feeding the grass can sometimes help.


Apply proprietary topdressing in spring and autumn spread at rates recommended by the manufacturer.

Regular mowing will gradually weaken weed growth and strengthen the turf.


Field Woodrush:

A flowering grasslike weed

Field Woodrush

A spreading grass-like perennial that is difficult to eradicate.

The weed has broad bladelike dark green leaves, fringed with silky hairs.

It is particularly noticeable when it produces its dark brown flower and seed heads, in March or April.


This weed is most common in acid conditions, so altering the pH is the best cure.

It is resistant to most of the weed killers now available.

Try applying ground chalk or limestone in late autumn or early winter, after mowing has ended, at a rate of 60g (2oz) per sq m

Do not use hydrated lime.


Speedwell:

A clump of a 'sreading' type of weed

Speedwell

This can be a problem in lawns as they are resistant to most of the lawn weed killers available to amateur gardeners.

As with Yarrow, lack of nutrients and weak grass encourages the spread of the weed, so a similar regime is required to eradicate it.

When mowing the grass do not cut it too close, as slightly longer grass will help smother the weed.

It is advisable to use a grass collector on your mower as Speedwell can reproduce from stem sections which otherwise would have been scattered by the mower.


Control:

A narrow fork like handtool for removing deep rooted weeds

Daisy Grubber

Many shallow rooted, rosette forming lawn weeds can be removed with a daisy grubber, while tap-rooted weeds can be removed with a long-handled weed tool.

Removal is best done when the soil is moist, firm in the turf after the weed/s have been removed.

Alternatively, weeds can also be treated with a herbicide gel brushed onto the leaves.

This will only affect the weeds treated.


Because of recent legislation there are now very few weed killers available to the amateur gardener.

Weed killers are best applied when the weeds are growing vigorously in spring circa Week 13

Always check the label to find out if it will work on the weeds in you are trying to kill.


Some varieties of weed may require a further two or three applications at roughly monthly intervals, however most lawn weeds are killed by one application.

The type of weed can often determine the weed killer to use and how often to use it!

In all instances apply in cool, moist, calm conditions to reduce the risk of damaging nearby plants with over spray or wind transfer.