Weeds – Identify and Manage

Know the Enemy 

The weeds are numerous.  The weeds grow most everywhere.  The weeds are like unwelcome houseguests that don’t know they stayed too long!


Weeds find weaknesses in the landscape – poor soil is an open invitation. Poor soil is hungry for nutrients.  Weeds don’t care.  Poor soil is dry and rocky.  Weeds don’t care.  Poor soil is in need of vegetation.  Weeds don’t care if they have good neighbors. They are quite able to adapt to less than perfect conditions. 



Weeds are classified into three groups – annuals, perennials, and biennials.
Annual weeds include crabgrass and foxtail.  These grow from seed in the spring, mature, produce seed, and die at the first frost in autumn. 

Lawns and gardens that are in need of good management are just asking for these intruders.

 
Biennial weeds include Musk Thistle and Burdock. This is the rosette of year one.

Biennials need two years to mature.  The first year they grow these rosettes above and store energy.  The second year they use that energy and flower and produce seeds.  At frost, they die.

This is the flower of Musk thistle, and Burdock. 


Perennial weeds include many familiar varieties.  Dandelion, Bindweed and Canada thistle are just some of them.
 
Bindweed and thistle spread by horizontal roots and are difficult to control.  If the plant is pulled, some of the root may remain.  This root will continue to grow and will grow a plant from each end, thus doubling your weed problem.


Using an herbicide is the best remedy for control.  The organic option of horticultural vinegar (20%), Acetic acid, clove oil or soap based herbicides will all weaken the plant and eventually cause the plants death if used repeatedly before the plant forms seed heads.

Lawn weeds are classified as broadleaf weeds and grassy weeds.  Some of the broadleaf weeds include plantains, white clover, and dandelions.


Clover indicates poor nitrogen in the soil.  Fertilize the lawn with Nitrogen, (the first element of the N-P-K) on the fertilizer label.

Plantains thrive in over-watered areas with compacted soil.  Reduced watering and core-aeration will improve the conditions and reduce plantain.

Core aeration

A good management of lawns is always to fertilize, water deeply, and mow high.

Grassy weeds are particularly difficult.  Annual grasses like crabgrass and goosegrass  can be controlled by using preemergents.  By applying preemergents before seeds germinate in the spring, seeds will not take hold and stop the cycle for annual grasses. 
 

Nimblewill is a warm season grassy weed that I have.  The control is difficult because there are few specific herbicides for these type of grasses.  A non-selective herbicide will kill anything that the herbicide is used on.
 

Quack grass is a cool season grass and spreads rapidly by underground rhizomes. 

Again, spot treating with an organic herbicide is recommended.  When the grassy weeds die from the herbicide application, a bare spot will be apparent.  And unless these bare spots are planted with a desirable grass seed, weeds will eagerly jump in to fill in the spot. 
Chickweed
Chickweed is an annual weed that spreads quickly.  Hand pull or scrape away with a spade.  Aerate and fertilize lawns to discourage its growth.

Nutgrass

Nutgrass is not a grass per se, but a sedge.  Specific herbicides for nut sedge will control this weed in the lawn.  Horticultural molasses, an organic product, also has good results. 
Buckhorn plantain
As a perennial weed, plantain can easily be removed by loosening the soil down the tap root with a dandelion weeder or flat head screwdriver.

Carpetweed
The annual weed, Carpetweed  can be controlled with a pre-emergent.  Carpetweed is commonly found in newly seeded lawns or in thin turf. A broadleaf weed herbicide can be used as a post emergent. I would use the organic herbicide with a clove or soap base.

Purslane
Control Purslane by hand weeding.  Cover vacated area with mulch.

Prostrate spurge
Prostate spurge, also known as spotted spurge, likes hot, sunny, dry areas.  Since this weed has a tap root (one long root downward) hand pulling can be ineffectual. Preemergents in spring can reduce seeds from germinating.  Weak lawns allow this spurge to take hold.  Fertilize and water to maintain a healthy, full turf.

Horticultural vinegar works well on this weed too.
 
Weeds are going to appear in any landscape. Taking a less than panicked attitude to weeds may reduce our knee-jerk approach to grabbing the strong, chemical herbicides. Acceptance of a ‘few’ weeds will go a long way to reduce harmful chemicals in the landscape.

Mulch 2 – 3” thick on flower beds will keep light from weed seeds, and reduce the number of seeds that germinate. Mulches can be pine, cedar, hardwood chips, grass clippings, leaves or straw. Even thick layers of newspaper can serve as a mulch. 
 

Weeds in the lawn may be more difficult to control, but a good maintenance program will limit their infestation. Mow grass high, don’t scalp the blades and don’t remove more than 1/3 of the blade at any cutting.  The high turf will shade weed seeds and keep soil moist.  Regular organic fertilizer applications can keep the lawn thick and healthy.

  
 
May the road rise up to greet you, and the weeds stay far away.  Enjoy your lawn and garden, relax……and have a great day!

Growing Pains of Summer -- Weeds

Organic Fertilizers was the topic of a discussion I gave at our local arboretum on Wednesday.  Cox Arboretum is one facility of our Five Rivers Metro Parks here in the Dayton, Ohio area.  We had a 'Lunch and Learn' program discussing the benefits of organic fertilizers. As the session progressed, I had several questions regarding Organic Lawn Maintenance, specifically weed controls.

So, since weeds are popping up all over, let's talk Organic Weed Control.

Weeds in landscape beds are easily maintained with mulch.  A two to three inch layer of any form of mulch will keep weed seeds from germinating. Hardwoods, pine needles, even newspaper will work well to smother weeds and if weeds to pop up, they are more shallow rooted and easy to pull.

Weeds in lawns, however are another matter!   The most important step to a weed free lawn is to 'mow high, water deeply'.  The tall grass shades any weed seeds.  Watering deeply develops deep roots of the turf and a healthy yard will choke out weeds.

Check out some of these bad boys!

 Plantain -  loves damp, heavy soil.  Organic fertilizers and compost will loosen soil, and help grass to push out weed.

This guy is bindweed.  Often mistaken for morning glory, bindweed is really hard to control.  It vines over shrubs, and perennials in the garden and can suffocate them.  Pulling doesn't work!  Digging the roots is effective eventually, but you need to be persistent.  Cut off flowers so they don't produce seeds. I try  to hit as many leaves as possible with an herbicidal soap or non-selective herbicide like   Burn Out II.  As a non-selective herbicide, applying them to just the weed is important, since this product will kill anything it is sprayed on, including grass and other desirable plants in the landscape.

Dandelion's  have a deep taproot.  Digging them will work if you get the complete root.  Here is a trick I'll share with you.  Weeds like a soil pH of 7.5 which is considered alkaline.  Grass likes a pH of 6.5.  So by adding a sulfur powder to your lawn or applying seed derived organic fertilizer like alfalfa (which is somewhat acidic),  the grass will thrive, and the weeds won't. The non-selective herbicides will work here too.

The other lawn problem that folks asked about is clover.  If you have clover, it is a sign of low nitrogen soil.  Fertilize to maintain a healthy lawn and reduce clover.  Clover is a nitrogen fixer which draws nitrogen from the atmosphere.  It is green, and if mowed, flowers are minimal. So maybe we can live with this one!

Crabgrass is an annual grass that is controlled easily.  Agralawn Crabgrass Killer is product is made from cinnamon bark will also control chickweed, and clover.  Apply to weed surface and results will be noticeable in 2-4 days. 

Once weeds get a hold in the lawn, there are several organic products that will dry out the leaves, causing the weed to eventually die.  One product I like is Horticultural vinegar.  Unlike kitchen vinegar that is 5% acidic acid, horticultural vinegar is 20%.  As the ingredient 'acid' hints, weeds don't like lower pH levels and pH levels of this product is about 4 - 5 - very acidic.

Manual methods effective in weed control.  Use the two tools at the end of your arms.

Weeds have been around for ever, and the range of tools to deal with them go way back to mid-evil times.

Modern technology in the herbicide industry is not proving to be better.  Chemicals like 2,4-D, are effective, but the health risks they pose are many.  Especially in children and pets whose bodies small, illness are widely documented.  Non-Hodgkin's lymphoma, endocrine disruptions, reproductive and development effects can all be attributed to chemical herbicides and pesticides.  Playgrounds, golf courses, and the home lawn and vegetable gardens have had tons of these chemicals applied.  Is it any wonder that we are turning to organic products for safe and effective controls for our lawns and gardens?

 

Thanks for visiting.  Leave a comment and let me know you were here.  Until next time - Claudia