Morpheuspa will look at your soil test results. I guess they didn't test for organic matter.

There might be some management issues. What is your general watering schedule? How often and for how long do you water?

How high/low do you mow?

When were the last two times you fertilized and what did you use?

The organic matter test was optional (an extra $6). If it is important I can ask for it next time.

Last year I used over-the-ground hoses and a programmable timer. I have four zones (one for each one of the areas in the pictures above). During spring and summer, I watered twice a week for half hour each zone. During fall the town has water restrictions and I watered once a week for one hour each zone. This year I am rethinking my strategy as I got tired of the over-the-ground hoses.

I mow at 3 inches all year round.

Last time I fertilized was a week ago when I used the Pennington Smart Blend seed (with 18% nitrogen). Before that, I fertilized late last fall when I used Scotts WinterGuard (32-0-10).

Thank you.

Boston is in the sand part of MA, so a CEC like that would be expected. With that in mind you need to get started on organic fertilizer at least once a year. I use it exclusively, but at least once a year will help.

Watering: Deep and infrequent is the mantra for watering. This is for all turf grass all over the place. Deep means 1 inch all at one time. Put some cat food or tuna cans around the yard, and time how long it takes your sprinkler(s) to fill all the cans. Memorize that time. That will be the time you water from now on. My hose, sprinkler and water pressure takes 8 full hours to fill the cans. Your time will likely be less. I like gentle watering. As for watering frequency, that depends on the temperature. With temps in the 90s, deep water once per week. With temps in the 80s, deep water once every 2 weeks. With temps in the 70s, deep water once every 3 weeks. With temps below 70, deep water once a month. Note that you have to keep up with quickly changing temps in the spring and fall. This deep and infrequent schedule works in Phoenix and in Vermont, so it should work for you. The reason for deep and infrequent is to grow deeper, more drought resistant roots and to allow the soil to dry completely at the surface for several days before watering again. If it rains, reset your calendar to account for the rainfall.

Your spring fertilizer application was about 8 weeks early. The grass is going to grow like crazy in the early spring even without fertilizer, so the idea is to let that happen, and then fertilize in late spring to replenish the nutrients. The fall fertilizer was perfect.

I have a question: my soil test recommends applying 125 lbs/1000 sq ft of limestone throughout the year. That sounds like a lot compared with your recommendation of 7 lbs/1000 sq ft. Why is that? Is limestone different from what you recommended? Thank you.

You're eventually going to require more than the 7 pounds (14 total this year) that I recommended, but I'm getting close to the maximum recommended amount per year of the limestone types I advised. Your soil CEC (how much in terms of resources it can hold) isn't very high, so adding more at a time risks having it wash out before it can bind.

Plus, the absolute maximum is 9 pounds per thousand at a time, twice a year, of very finely ground calcium carbonate. Adding more will pale the lawn pretty badly and you end up with yellow grass.

dchall,

Is it still recommended to water (Deep means 1 inch all at one time) in sandy soil vs. more frequent watering for a shorter time?

Will the water leach right through the sandy soil and not be available to the grass roots?

thanks

Thank you, morpheuspa.

I found Mag-I-Cal (22.5 lbs of pellitized calcium) in my local store. According to the bag, it covers up to 5,000 sq ft which is exactly my lawn's size. But my math says 22.5 lbs / 5,000 sq ft equals 4.5 lbs / 1,000 sq ft which is less than your recommendation. Does it mean I should buy two bags?

Go ahead and put the whole 125 lbs of lime per 1000 square feet. It will not cause problems. This is a typical agricultural rate. It is not so soluble that it will wash out of the soil. The lime will raise the pH, and drop the levels of soluble aluminum that are toxic to plant roots. It will also raise the soil pH a bit.

Go ahead and put the whole 125 lbs of lime per 1000 square feet.

A bit inconsistent with the advice:

See lime advice.

Get two bags and apply the whole seven per K at once--it will be fine.

125 per K...well, that wouldn't be fine. Not at all, not using Mag-I-Cal. It probably wouldn't kill too much except your soil biology, but the lawn will look terrible for months. So don't do that.

Do an experiment. Put the whole 125 on a small area. You won't cause any damage unless you smother the grass. Lime is not soluble enough to bother soil microbes. The increased pH will increase their activity level.

I have written to Encap, Pennington, SoluCal, and Jonathan Greene about how much can be put down at one application and if it was ever okay to go over that amount. So far I've only heard back from Jonathan Greene (MagiCal manufacturer) and the answer was the maximum that can be put down at one time is 9 lb/K. I would trust manufacturers to know their product and its limitations.

There's two types of lime I see at the store, one that costs about $3 a bag and a "fast acting" kind that costs a lot more and covers more area. The $3 one I think you can do up to 50lbs per thousand sq ft, but the more expensive one claims to cover 5,000 sq feet with one 30 lbs bag, so I'd be very hesitant to apply it at 20x bag rate (125 lbs).

Maybe someone can explain the difference between the two and clarify which lime is being recommended at 9# and 125# application rates .

The more expensive kind is what I recommend; it's far more finely ground, so the surface area to volume ratio is far greater, and it dissolves faster in an acidic environment (such as the soil we're adding it to). Perk rates are still slow, however--calcium does not move quickly through the soil. That's the one to put down at a max of 9#/K, and I've definitely observed yellowing in grasses where it's over-applied.

Cheaper calcitic lime is often an unknown. Some is quite good and fast, some is not.

Cheaper dolomitic lime is called for when some magnesium is required and you don't particularly care about speed. The sieve size is often much larger, so it takes longer to reach the soil. I still wouldn't recommend rates much over 40#/K at one time, however, with a six month rest between applications. There are certainly well-ground dolomitic limes that are much faster, but...suffice to say that I've never encountered one locally in many, many years of haunting the aisles.

Some of the issue is the bacteria and fungi that are natural to your soil...many of which have more limited pH ranges and lower tolerance to pH alteration than they do to almost any other change. It takes time for the soil to adjust by having the new organisms blow in, or reproduce to dominate if they're already there. Blowing away the bacteria and fungi in the rhizosphere is an invitation to problems. They'll fix themselves--eventually--but why set 'em off in the first place?

beckyinrichmond

I have written to Encap, Pennington, SoluCal, and Jonathan Greene about how much can be put down at one application and if it was ever okay to go over that amount. So far I've only heard back from Jonathan Greene (MagiCal manufacturer) and the answer was the maximum that can be put down at one time is 9 lb/K. I would trust manufacturers to know their product and its limitations.

Becky - farmers routinely apply much more than this - several tons per acre, or more than 100 lbs per 1000. Go to your local golf course and ask them how much they apply.

Becky - farmers routinely apply much more than this - several tons per acre, or more than 100 lbs per 1000.

You're quite the busy bee, azdoctor.

You ever heard of an "acre furrow slice?" Or incorporation? If so, do you have any supporting literature that surface applied lime will affect more than the top 1-2" of soil? Or that raising the PH in that top 2 layers above 8.5 is not detrimental to turf?

The depth to which surface applied lime moves depends on soil texture and mineralogy. In a sandy soil, all things are likely to move more than in clay soils. In soils with variable charge (highly weathered, sub-tropical or tropical soils), the CEC will increase as the pH increases. This means that the calcium in the lime will be held by the newly created exchange sites. Lime can raise the soil pH to about 8.2, and no more. You can test this by dissolving lime in water and measuring pH. (I'm talking lime, NOT quicklime or burnt lime which should not usually be used as soil amendments.)

Your point is a good one, though. Unless the soil is disturbed by aerating for example, surface applied lime may take a long time to move throughout the rooting zone. On the other hand, pH 8.2 soil makes a pretty good grass growing medium.

Oh, and and acre furrow slice is usually considered to be 21,780 cubic feet of soil - one acre, one half foot deep. In most soils, this is about 2,000,000 lbs of soil.

On the other hand, pH 8.2 soil makes a pretty good grass growing medium.

Not by any literature I've read. Not that it's deadly, but per university and turf specialists ( e.g. PACE) a PH over 7.5 will adversely affect cool season grasses.

Oh, and and acre furrow slice is usually considered to be 21,780 cubic
feet of soil - one acre, one half foot deep. In most soils, this is
about 2,000,000 lbs of soil.

Then you are also aware that many/most soil test lab/university extension lime recommendations are based on that full 6-6.7" soil profile to be incorporated into the soil and not for surface application.

Here in Arizona, we grow beautiful turf on pH 8.2 soil. No problem...

Your soil biology is used to it, and has been since at least the last Ice Age. Even so, iron availability is abysmal at that pH, and many other minor and trace elements are a battle.

By the same token, I've adjusted a rhododendron to do very, very well at a pH of 6.8 in the gardens, but it took me years of carefully nudging things along. Rapid adjustment would have been an exercise in extreme chlorosis and watching it die. Even doing that, I still enhance iron levels monthly through the season...just in case.

Hi morpheuspa,

How does weed control come into play in your recommendation above? Does it complement it or should I refrain from applying any kind of weed control? Thanks again!

You can weed control at will! You can also feed the lawn at the correct times (spring, late summer, and fall) without interacting with this.

Almost every treatment I can think of will be just fine with this resource addition, so there are no restrictions.

But the starter fertilizer has nitrogen itself. Wouldn't that be too much nitrogen (starter + feed)?

Any comments? Should I apply the regular feeding (for example, winterizer in fall) plus the starter fertilizer recommended here? Or will that be too much nitrogen and will kill my grass? Thank you.

It appears to me all the nitrogen your grass needs is covered in Morpheus' plan. I think he was referring to weed control, you can do it anytime, it won't interact with the feedings.

Feedings should not exceed 1# of nitrogen in a period of one month, although slightly greater amounts can be applied without damage. Starter fertilizers vary in nutrient quantity, e.g. 18-24-6, 24-25-4, 11-28-9, etc. Some contain fast release, some are slow release. Bag rates vary, but I believe morph's recommendations are for 1# of P to be added at each application, which would be greater than most recommended bag rates.

You should calculate the amount of N you are applying per your specific starter and application rate and then you can make up the difference to total 1# N. Organic fertilizer application is another matter.

morpheuspa: You cannot tell soil texture from the CEC! There is a relationship, but not a direct one. I can show you very sandy soils with a CEC of 8 meq/100g and I can show you a clay soil with 8 meq/100g. I can show you a sandy soil with a CEC of 20 meq/100g or a clay soil with a CEC of 20 meq/100g.

This is not a critical issue, but you have it wrong!