There are two problems that I was asked about this week and they may be ones that also affect your gardening endeavors.
The first is brown patches in lawn which often people mistakenly think of grass grubs as the cause. This is not to say that grass grubs don’t cause problems eating the roots of grasses but they are in the main seasonal. At any time of the year you may find a few white grass grubs in your gardens or lawn but the main populations start of from eggs laid deep in the lawn some time about November December when the beetles are active .
During their short period of life they are mating, laying eggs and eating holes in your plants at night. The grubs will hatch out and start feeding on the plants roots. If the soil becomes very dry as in a drought they will stop eating and lay dormant in the soil till the autumn rains moisten up the earth. Then they will continue eating roots towards the surface.
If in autumn you lift a square of lawn you may find a number of the grubs in the top 50mm of soil. If there is several in a square foot of area then it is worth while treating for control.
Control methods are either Wallys Neem Tree Powder or Wallys 3 in 1 for Lawns. Brown patches of grass at this time of the year is unlikely to be grass grub damage. It could be porina caterpillars which come out of their earth tunnels at night time to feed at the base of the grasses. This will cause bald patches. In gardens they may chew through the trunk of young seedlings and next day you will see the top of the seedling laying on the soil shriveling up in the sun.
Control treatment for lawn and seedlings is simply spraying the grass with Wallys Super Neem Tree Oil late in the day onto the recently mowed lawn. Like wise spray the seedlings for total coverage including the trunk near soil level. The porina when they come up to feed at night will get a dose of Neem and stop eating to starve to death.
The next possible reason for dry brown grass is a Thatch Problem. Thatch in lawns is the debris that builds up on top of the soil making a layer of organic rubbish. Over time unless treated the layer becomes dense and several mils tall. You will notice that when walking on the lawn a spongy feeling like walking on a thick carpet.
Thats the thatch.
When it rains or you water the thatch collects and hold the water in it layer which makes the grasses feeder roots grow up into the thatch for moisture. That not only makes the grasses weaker but also go brown when the thatch dries out. Sun and wind will dry thatch leaving the grasses without moisture so they will go brown.
The easy way to solve the problem is to use Wallys Thatch Busta on your lawn.
You dilute the product and spray it over a freshly mowed lawn or even better apply with a Lawn Boy if available. Thatch Busta is a high food which feeds the microorganisms to increase their populations and they will break down the thatch converting it to food for your lawn. The area needs to be kept lightly moist while this is happening and if no rain give a light watering once or twice a day to ensure the thatch is kept moist.
Warmth is the other requirement for success and at this time of the year there is ample warmth. Thatch Busta is best used in spring and autumn when there is adequate warmth and moisture from rain or dew.
Now the real problem of brown patches in the lawn if none of the above is what we call Dry Spot. Dry spot is when the soil surface tension caused but a period of dryness is such that water will not penetrate into the soil and instead sheds off into the surrounding area where it will sink in. The result is a brown area of grass with lush green grass around the perimeter. The easy way to solve dry spot is to fill the watering can with warm water, give a good squirt of dish washing liquid into the water and lather up with your hand. Water the soapy water over the brown grass and it will break surface tension so when you water or it rains the water will penetrate and the brown grass will green up again.
You will have likely seen in dry times playing fields that have gone brown looking like all the grasses have died. Not so once the rains come they will bounce back green, they were only laying dormant though lack of moisture. It takes a real dry drought for the sun to bake the grasses roots in the dry soil to kill the grasses. Dry spot or dry areas can also occur in your gardens and the soapy water will also fix the problem. Dry surface tension over larger areas are a cause of concern when it rains for the first time as the water cant sink in and flooding occurs. I always water regularly and in particular before rain to prevent that happening.
Now the next problem is container plants in big containers such as half wine barrels. Perennial plants such as shrubs and trees in those containers need root pruning every two to three years. That means lifting the plant out, cutting off bottom third of roots, putting fresh compost into the container (to height of removed roots part) and popping the tree/shrub back in. Not easy to do but if not done the plant becomes root bound and eventually dies.
Now some containers have either a bulge in the middle as in some types of urns or the top is more narrow than the container below. Containers like that should never be used for planting perennials in, only annuals. Always make sure the top of a container is the widest part and no pregnant like bulges. But not all is lost if you have the wrong type of container with a shrub or tree growing in it. After say 3 years in the container with a sharp long knife cut four wedges out of the root mass at the four cardinal points. Cut as deep as you can and remove the roots and soil. Then sprinkle some Blood and Bone and Sheep Manure pellets down the wedge holes and then fill with fresh compost. You may need to repeat this operation every two years and cut your wedges in a different area from last done.
Another way is if you have a drill bit that is about half a metre long and about 4cm wide you could drill some holes down into the container to cut roots and then fill holes as above.
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