The Weekly Weeder: Natural Weed Control

Notice the old leaves under the rose, and the 4 x 8 sand paths.

            Weeds are taking over neglected portions of our cities and countryside, making them ugly, disorderly and unsafe.  Flowering weeds are often ugly, always disorderly, and once they dry out, they are a fire hazard.  If not killed before going to seed, they spread themselves around; they are a nuisance that multiplies.  Whole city subdivisions have burned in recent decades, and some small towns as well.  Oregon, Washington and Arizona burn in the summer, California in the fall, and large expanses of the Great Plains in dry winters.  When city weed codes are well enforced, cities don’t burn. 

          The most dangerous weeds are annuals that seed and dry out in a season.  They make many seeds, some of which can last for years in soil before they sprout or rot.  But their roots don’t need to be pulled to kill them; all of their top growth comes from their crowns, the part of the plant between the roots and the top.  Cut them under the crowns, and they are gone.   

          You can cut them under their crowns with scissors or a knife, which is great for going after individual weeds, but is relatively slow.  Still, this is the best way to handle seeded puncture vine, a noxious weed that pops bike tires as well as poking bare feet.  Cutting or pulling are the only ways to take weeds out selectively in lawns, beds and borders.

          You can also beat the crowns out of the soil wholesale with a string trimmer.  This works best when the plants are young and not yet seeded, and the soil is relatively soft.  It has to be repeated to catch newly sprouted annuals and re-growing perennials.  Done often and long enough, it can kill out perennials as well.

          You can mulch with leaves, compost, wood chips or bark to smother small plants and stop seeds from sprouting.  Most very small seeds need a touch of sunlight to sprout, and nearly every newly sprouted plant can be easily smothered with 2 inches or more of dense mulch.  Avoid fine bark and non-sifted bagged bark with fines; bark’s natural preservatives leach downward and kill soil life. Larger barks do not kill soil, but ¾” nugget and larger bark are not dense enough to smother at 2” deep.  Walk-on fir bark is most effective at smothering and staying put.

          Leaves are the most effective mulch, though some tend to blow around a bit.  They dry quickly on the surface and make a lousy seed bed for whatever falls on them.  Leaves and compost also feed soil life, which makes the soil soft for pulling weeds and provides habitat for good bugs like soldier beetles, spiders, centipedes, millipedes, ground beetles, and earwigs.

          You can spread an inch of 4 x 8 sand (river sand sifted to ¼-1/8 inch) to bring seeds up and then cut under them with a hula hoe (AKA scuffle hoe and stirrup hoe), which is made to slide under crowns.  Sprouting seeds put their crowns at the top of the sand, making it easy for the hoe to slide beneath them.  This is particularly good for maintaining paths and open areas.  4 x 8 sand is also good for establishing lawns from seed, as it covers the seed, brings it up by warming the soil, and protects roots and crowns as they grow.

          Roundup herbicide (glyphosate salts) should generally be avoided, simply because it also fertilizes for broad leaf and annual plants and feeds worms and pill bugs, which in turn attract moles.

           

 Rycke Brown, Natural Gardener       541-955-9040        rycke@gardener.com

The Natural Gardener: Leaves build soil and stop weeds

Leaves are not waste and should not be wasted.  They are the best and cheapest mulch around for stopping weeds, building soil and providing food and habitat for predator bugs.  This retired Natural Gardener used to haul bags of excess leaves away for free to customers through the fall, spreading them to reduce work and help preferred plants grow for the rest of the year.  Now I am taking leaves for my own yard only. I prefer leaves in clear plastic bags.  I don’t take bags heavier than 50 pounds, or with too many sticks.

Nearly every other mulch is a seedbed as soon as it is spread.  Seeds fall on top, find a crevice and grow.  Leaves dry out on top, and so make a lousy seed bed for anything that falls on top of them.  Even a thin layer stops small seeds beneath them that need sun to sprout.  Two inches or more can smother most seeds as well as small plants and feed the soil enough to soften it and make it easier to pull the weeds that grow. 

The deeper they are laid, the more weeds they can stop and the more they build the soil and soften it.  A foot or more will grow huge vegetables, while they rot and worms and pill bugs eat them over the course of the gardening year.  That increased fertility can be maintained with only a few inches per year. 

The only thing comparable to leaves for building soil is compost, which leaves become without any special help, if they aren’t mounded.  A mound sheds water, within which leaves can stay dry and not decompose for years.  Spread flat, a foot of leaves is the equivalent of 6 inches of compost, which can also grow huge vegetables, plus can be used to build beds year-round.  In late spring and summer, exposed compost also dries out quickly, but in winter, it is a seed bed for whatever falls on it. 

You can start small cool-weather seeds by spreading an inch of compost on top of leaves and scattering the seeds in it; for larger seeds in late spring and summer, scatter seeds on the leaves and cover them with compost.  You can also poke large seeds like peas, corn, beans and squash into the leaves to where it is moist to maintain that cover of dry leaves while they grow.  You can plant starts into leaves as well, with or without compost on top.  

You can warm the leaves to help the seeds and starts grow faster by putting rocks around them.  Rounded river rocks, just small enough to move with one hand, are easy to move and hold heat through the night, when the plants need it most.  The smaller the rocks, the hotter they get but the less heat they hold through the night.  Larger rocks can be used to provide a solid edge for mulch beds and keep them from spreading.

Leaves should be removed from buildings, pavements, gravel, and paths.  They should be left and built up on open ground, in beds and borders, and mulch-mowed into lawns.  If you have too many, put your excess in clear bags and call me.

Gardening is easy if you do it naturally.  Litter is tagging, marking the territory of the disorderly.

Rycke Brown, Natural Gardener      541-955-9040             rycke@gardener.com