by Paul Heinze, Greenview Organics
Spring is almost here and it is time to start thinking about your lawn, and how you are going to care for it this coming growing season. Your lawn has been laying dormant under a nice blanket of snow all winter, so it should spring back to life when the warm weather arrives this spring, especially if it was fertilized properly last year.
Now you may ask, what kind of fertilizers should I be using? With all the different choices out there (10-10-10, 28-0-3, fertilizer with crabgrass preventer, organic fertilizer), it gets a little confusing. Let’s try to take the confusion out of it. First you need to know what your lawn needs. A simple pH test on the soil of your lawn will tell you if your soil is acidic or alkaline. Most soils in the Chippewa Valley are on the acidic end of the pH scale. Some lawn weeds actually thrive more in soils that are on the acidic side of the pH scale. Like the pesky dandelion; it likes soils that are more acidic. With its long taproot it will go down deep to find calcium in the soil and bring it to the surface. When the dandelion dies, it will leave the calcium-rich leaves on the surface to help balance soil pH. This is nature’s way of balancing the soil pH. By adding lime, we can balance the soil pH to a more desirable level for the grasses and not so much for the dandelions. I like to see the pH levels between 6.4-6.8 for optimum nutrient uptake by the lawn grasses.
Next, let’s look at the three most common nutrients in lawn fertilizers. Those are the three numbers you see on a fertilizer bag. I would recommend a soil sample taken by yourself or a lawn care professional. These samples are then sent to a lab for analysis to determine the available nutrients in the soil, mainly phosphorus, which is the second number on a fertilizer bag, and potassium is the third number that you see on a fertilizer bag. It is important to know what the nutrient levels are in the soil of your lawn; mainly the phosphorus, potassium, and the pH level. In the state of Wisconsin there is a phosphorus ban on turf fertilizer that was enacted by the state legislature, and Gov. Doyle. The ban was enacted to prevent the overuse of phosphorus in the environment. The ban only allows for phosphorus to be applied if a soil test calls for it, or it is a newly seeded lawn. Phosphorus has been long recognized as a factor in plant and algae growth in Wisconsin lakes and streams. By having a soil test you can determine whether your lawn needs extra phosphorus or potassium. It has been my experience, that if lawns have been fertilized over the years and the grass clippings have remained on the lawn, you will have adequate levels of these nutrients, but only a soil test can tell you that. Nitrogen, the first number that you see on a fertilizer bag is a nutrient that is not very stable in the soil. Nitrogen tends to leach into the soil, volatilize into the air, or it is tied up in organic matter in the soil. Generally the recommendations for nitrogen on lawns are to have 2 to 3 pounds of nitrogen per thousand square feet applied during the season.
Let’s take a look at synthetic fertilizers. These fertilizers are made to be readily available to plants. That is why you get a green up of the lawn soon after application of synthetic fertilizers. However, synthetic fertilizers do nothing to build organic matter. They are made with high concentrations of salt and other chemicals, which tend to kill the beneficial microorganisms and earthworms in the soil. Your lawn will become more and more dependent on chemicals to fight off disease and other fungal infestations. The soil also becomes more acidic, so you need to add more lime; it becomes lifeless of the beneficial microorganisms and earthworms that the soil needs to sustain a healthy disease and fungus-free lawn.
Organic treated lawn programs feed the soil, which then feeds the lawn grasses; synthetic treated lawns feed the grass only and do little to benefit the soil and roots of the lawn. An organic treated lawn is a process of building the soil with organic matter, and by leaving your lawn clippings on, you add even more organic matter. There is free nitrogen in lawn clippings: 1 to 2 pounds of nitrogen per thousand square feet per season. By using organic fertilizers and compost teas on your lawn, you start a process of building the beneficial microorganisms and earthworms in your soil, which help to break down the grass clippings and thatch and other organic matter in lawn, releasing nutrients back to the grass plants. We are in a sense recycling grass clippings back into the lawn along with the organic fertilizer creating a “Green Lawn Naturally.” Organically treated lawns have a denser, longer root system; these roots go down deep and some of the microorganisms attach themselves to the roots helping to extract macro- and micro-nutrients from the soil. With the deep root system, your lawn will require less water during the hot summer months. There are fertilizer products out there that say they are organic-based. These products still have synthetic fertilizer blended with organic fertilizer making you think you are buying something that is natural.
Organic treated lawn programs feed the soil, which then feeds the lawn grasses; synthetic treated lawns feed the grass only and do little to benefit the soil and roots of the lawn.
What about the weeds? How are you going to control the weeds that tend to creep into a lawn every year? With an organic lawn program that is more of a challenge. Unfortunately, there are no organic lawn weed killers that will work for those pesky dandelions and other broadleaf weeds, and the seemingly encroaching crabgrass. There are organic weed killers, but they kill everything including your lawn grasses. An organic lawn care program looks at balancing the soil pH and nutrients in the soil, by adding organic fertilizer and compost tea to promote the growth of the beneficial microorganisms. This in turn creates a thick, dense lawn that will crowd out the weeds. Crabgrass especially does not like competition; you will notice that crabgrass grows in areas where your lawn is thin. (Those areas by your driveway, street, boulevards, and other high-traffic areas.) Some of these areas also receive high concentrations of salt during the winter months, which makes it harder to grow lawn in the first place. Crabgrass seems to have a higher tolerance to soils with higher salt concentrations. This is another reason we want to stay away from the higher salt concentrated synthetic fertilizers. Weeds can be controlled in an organic lawn by digging out the dandelion, and other weed roots as much as possible. In some cases where lawns are severely infested with weeds, it may be wise to kill off the entire lawn and start over. Areas that are thin need to be re-seeded with desirable lawn grass seed.
I think that everyone knows that weed killers, chemical fertilizers, and other chemicals that are applied to lawns are not good for the environment, our families, and our pets. There’s a reason why lawn care companies are required to post a lawn sign after an application of fertilizer, weed killers, and other chemicals. I am not going to get into all the details of why chemicals are bad for you and the environment. I think that people are smart enough to find out that information on their own, and to educate
themselves. There are many resources on the Internet and other resources that will tell you all about the dangers and side effects of using lawn chemicals.
Tips for an Organic Lawn:
Set blade 3 inches or higher, and cut no more than one third of the grass blades off at a time. Tall grass is more stress tolerant, shades the soil (conserving water, especially during the intense summer heat). It also helps prevent weed seed germination and has a larger root structure, which also increases uptake of water and nutrients. The last mowing of the season can be mowed lower.
Keep mower blades sharp.
Mow when grass is dry, in cool part of the afternoon or evening.
(Mulch clippings) Mulching reduces the need for fertilizer since important plant nutrients are returned to the soil.
Water between midnight and 8 a.m.
Water deeply and only when needed (every few days, not every day).
Water 1 inch at a time (set a rain gauge out).
Cancel a scheduled watering if a recent rainfall has occurred.
Proper watering ensures a denser lawn and allows the turf to compete more effectively with weeds and will also reduce fungus and pest problems.
Use only organic fertilizers. Some products out there say that they are “Organic Based”. These products still have synthetic fertilizer in them, blended with organic fertilizer.
Properly conditioned soil provides vital nutrients to plants, retains water, and supports many micro-organisms.
Balance the soil pH. A soil pH between 6.4 and 6.8 is critical for nutrient uptake by the grass.
If soil is compact, aerate your lawn.
Over-seed areas that are thin.
Weed control in a organic lawn program is more of a challenge, but following the above guidelines, lawn weeds should be at a minimum.
Spot treatment of organic weed killer or by pulling with a fish-tail weeder may be necessary from time to time. Severe weed infestations before starting an organic lawn care program may require chemical weed treatments, and should only be handled and used by responsible professionals (Unfortunately there are no organic lawn weed killers).