BaySense

What is the market share of organic lawn fertilizer?

Back40's new comment on compost, fertilizer and gypsum got me wondering about market share (and mind-share) for different lawn fertilizers. I don't know the answers yet, but I do have some inklings:

- Someone on staff at the local garden supply store thought organic was under 10% of their fertilizer sales. When I inquired about buying compost for my lawn, she looked puzzled.

- A professional landscape designer suggested to me last year that organic fertilizer doesn't work very well.

UPDATE. An article in Discount Store News (1999) titled: "Savvy marketing feeds fertilizer sales" :

none of the major [lawn & garden fertilizer] players seems very anxious to dabble in organic, chemical-free fertilizers, which are hard to find at retail.

Fertilizer representatives said while customers may like the concept, some organic products haven't performed as well, so they're keeping most of their focus on a sure thing--npk formulations

When to fertilize lawns? Answer may differ for compost vs. chemical fertilizer

In a comment on one of my BaySense posts, Back40 explains:

If you use chemical fertilizers such as Penn State recommends rather than compost as CBF recommends then it is best to split it into 3 smaller applications to get total recommended nutrients. This reduces runoff and avoids burning your worms.

Though your PH is good you may still wish to add calcium. To do this use gypsum rather than lime. Gypsum also adds sulphur.

Compost really is a good idea. It adds carbon and improves soil tilth and absorbency. Leaving mulched clippings in place will achieve the same thing over time but compost can give you a head start.

The definition of "lawn" may be an issue. Grass needs slightly different soil fertility than other species such as clover [...]

Cool. Thanks!

Earlier in the year, back40 had other insightful comments about clover, including where to buy seeds. I already have some white clover, and plan to add some red next year.

My next questions:

(1) If I go with compost and gypsum, how much should I add per 1,000 square feet in the fall?
(2) Where am I likely to get good quality compost and gypsum at a reasonable price?
(3) What -- roughly -- is the range of N-P-K percentages (nitrogen-phosphorous-potassium) that I can expect to get in "typical" compost?

Trying out Penn State's agricultural lab -- I get soil test results back

Part 2. After sending in a sample of soil from my front lawn, I just got the test results back. The turnaround time was about ten days. Here are the results, along with Penn State's recommendations and explanatory comments:

1. Soil nutrient levels:

Soil pH ------------- 6.8* (optimum)
Phosphorous (P) - 11 ppm** (well below optimum)
Potassium (K) ---- 64 ppm** (well below opt.)

2. Limestone [needed]:

NONE

3. Fertilizer needs:

[Note: Penn State's recommendations for fertilizer (below) conflict with the advice of Chesapeake Bay advocates like CBF, who recommend fertilizing only in the fall.]

FERTILIZER* .... RATE: lb. per 1000 sq. ft.**
--------------------------------------------------
24- 5-10 .............. 4.0
18- 6- 6 ............... 5.5
13-13-13 .............. 7.5
10-10-10 ............ 10.0
10- 6 - 4 ............. 10.0
10- 5 - 5 ............. 10.0
9- 4 - 4 .............. 11.0
8- 4 - 4 .............. 12.5
7- 5 - 5 .............. 14.0

*Select only one
**Apply three times during the growing season

For a simple fertilizer program that will provide adequate quantities of nitrogen, phosphate and potash to turf based on your soil test results, apply one of the fertilizers listed on the left at the rates specified three times during the growing season for a three-year period. Apply once in mid-spring (May), once in late summer (September), and once in the late fall (November) each year [...]

4. Nutrient Needs (lb/1000 sq. ft.):

N: ....... 3-4
P2O5: .. 3.5
K20: .... 3

The individual nutrient needs for optimum turf growth are listed [above]. These needs will be met by applying fertilizer materials listed in the above table three times per year for the three-year period.

5. Laboratory results:

pH: 6.8 [1:1 soil:water test method]
P (lb/A): 22 [Mehlich 3 (ICP) method]
Exchangable cations (meq/100g):
-- Acidity: 0.00 [Mehlich buffer pH method]
-- K: 0.16 [Mehlich 3 (ICP) method]
-- Mg: 2.32 [Mehlich 3 (ICP) method]
-- Ca: 7.44 [Mehlich 3 (ICP) method]
-- CEC: 9.9 [Summation of cations method]
% Saturation of CEC
-- K: 1.7
-- Mg: 23.3
-- Ca: 75.0

Comments:

1. Lime may be applied at any time of the year, although fall application is considered optimum [...]
2. If the lime recommendation exceeds 100 pounds per square feet, split the recommended amount into 2 or more separate applications 4 to 6 months apart [...]
3. When possible,, use fertilizer containing 30% or more of the total nitrogen in a slowly available form as water insoluble nitrogen (WIN) or controlled release nitrogen (CRN). This information is provided on the fertilizer label.
...
6. NITROGEN RECOMMENDATION: There is no reliable test for evaluating the amount of nitrogen (N) in soils that is available to turfgrasses over the growing season. The recommendation on the front of the report is the amount of actual N that needs to be supplied anually to ensure optimum turf quality.

Lawn care -- trying out Penn State's soil-testing lab

Part 1. Since the fall fertilizing season is upon us, I'm going to get the soil from my lawn tested to see what shape it's in.

Although Maryland Cooperative Extension no longer provides a soil-testing service, they do provide a list of seven labs that will test your soil for a small fee. I chose Penn State because it's the only one on the list with a link to a website.

Here's the process:

1. Select the appropriate form from the Penn State website. For home lawns there's a form for requesting a single sample and another for multiple samples.
2. Take a soil sample (about 1/2 cup) and seal it a zip-lock bag.
3. Mail the soil sample, the filled-in form, and payment ($9.00 for basic testing of one sample) to the lab at:

Penn State Agricultural Analytical Services Lab
Tower Road
University Park, PA 16802

They'll test the soil and send you a report that covers "pH, acidity, Mehlich 3 phosphorous, potassium, calcium, and magnesium and lime fertilizer recommendations." As for nitrogen, the form states that "the nitrogen recommendation is based on crop response."

Runoff from lawns in Maryland - facts are still scarce

Here's what Tom Horton wrote (in Turning the Tide) in 1991:

Very little attention has been paid to monitoring the runoff of chemicals from [lawns in Maryland, a] rapidly growing acreage.

I think his statement remains true today: little is known, and the acreage is still growing rapidly.

More from his book (p. 61):

University tests results indicate that, in general, there is less runoff of nutrients and pesticides from turf grass than from croplands. But unlike in agriculture, the application of fertilizers and other chemicals tend to be performed by huge numbers of amateurs without much supervision or education.

Some basic numbers from about 15 years ago:

In Maryland, the acreage in lawns for homes, golf courses, cemeteries, median strips, and grounds of public and commercial buildings covers nearly 700,000 acres -- more than 10 percent of the state's land surface. (Corn, the largest crop in the state, covers about 650,000 acres.)