NEIGHBORHOOD GARDEN FOR OCTOBER 11, 2008

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MULCHING

BY GLADYS JEURINK

 

          Mulching is a good thing!!! Some of the good things about mulch includes:

·        It keeps moisture in the soil. I like to put on 2 to 4 inches just after a rain. 

·        Mulching also prevents erosion during a hard rain. The rain hits the mulch which slows down its force.

·        Mulching also absorbs a great deal of the moisture and thus helps to keep the surface from drying out.

·        If you walk in a flower bed it will compact the soil but since mulch is spongy the effect will be less.

·        During the very hot days of summer the soil dries out rapidly and you need to water more often but a layer of mulch is a good temperature regulator.

·        In winter it will keep the soil colder or frozen on a warm day and thus help prevent the soil from thawing and then freezing again which raises the soil and lifts out roots. In a long warm spell the roots may start growing only to be frozen later when the spell ends. It also acts as a blanket so the soil does not become frozen as deep.

·        The blanket affects roots in summer too as the heat cannot penetrate as deep.

·        If you have areas that reseed themselves, you may need to leave the soil exposed until they come up. When your plants are up the mulch can be applied, but don’t put it directly on the stems to cause rot. By the same token, wherever you have mulch deep enough it will prevent weed seeds from sprouting. 

·        Transplant survival is aided by mulch. The plants were probably crowded into a 2 to 3 inch pot so can’t get water from a large area.  If roots are too crowded, carefully pull them apart before planting so that they don’t continually go in a circle. Water them well and then add mulch to keep the soil from drying out.  This will help to get the roots established so they can support the stem and leaves.

·        Mulching will encourage earthworms nearer the surface to eat the organic mulch.  This enables them to create more “castings”. One can buy castings but not cheaply so why not make your own.  With a good worm crop plus all the other critters such as fungous, bacteria, etc., you might have to renew the mulch again in a season.

·        As the mulch is slowly digested by worms, fungous, bacteria, etc., nutrition is added to the soil.  Depending on their activity, especially earthworms, one needs to watch the level of mulch.

·        A good example of necessary mulch is under roses.  The fungous spores of black spot drop off the affected plant or are already in the soil.  Then when it rains and the drops hit the spores, they are splashed back onto the leaves.  The mulch keeps this from happening. 

·        Tomatoes especially need a mulch to keep the soil water even to prevent blossom end rot.  They need to have an even amount of moisture, not a puddle of water, in the soil at all times.

·        On a perennial bed, mulch in winter will keep the soil cool longer so the plants don’t come up so early in a “false early spring”, and then get frozen. Some of my perennials are not zoned for 5 so to keep them alive, I put a cage over them and fill it with compost after a hard frost.  This way they will be warmer in winter and stay cold longer in spring in case of a late frost. Our native plants do not need this “baby sitting” but mulch is worn down by spring and they can come right through it.

        

There are a few things to be concerned about when mulching:

·        One is disease. Do not put diseased plants in your compost pile unless you are sure it gets hot enough to kill it, usually at least 160 degrees F.

·        If you use a sawdust mulch, all the soil critters will work on it and use up the nitrogen doing so.  Later on this will be released back into the soil, so when I use sawdust in any bed I also put lawn fertilizer on top to keep food available.  Lawn fertilizer is always higher in nitrogen than anything else.  Wood chips are not as bad since they break down so slowly.

·        Too deep a mulch is not good as it can keep oxygen from getting into your roots and may keep everything so wet that root or stem rot occurs.  When I see a tree with 1 to 2 feet high mulch volcano around it and pushed up to the trunk, I am tempted to write down the date to see how soon the plant dies.

·        Grass clippings are a good mulch if dried before using.  A deep layer of fresh green mulch is slippery, smells terrible, and heats up. But the dry grass returns nitrogen to the soil.

·        Some people, especially those with Hosta, do not like mulch at all as slugs love to spend their days in cool mulch and eat the plants at night. There is a slug bait now (iron phosphate) that you can get to put under your Hosta that feeds iron to the plant, doesn’t poison your dog or cat, but kills the slugs. It is sold under different brand names but available in most garden centers.

Mulch is very good for your garden and landscape but like many things, must be used wisely and appropriately!!!

Copyright 2008