Spring is a good time to give a little extra effort to your lawn work. The dividends will be a better lawn and less need for weed control and other lawn chores during the hot summer.
Kentucky bluegrass, our most common lawn grass, and most other lawn grasses used in temperate regions respond best to treatment when the weather is cool. This makes spring effort especially important.
If you are willing to do a little more in spring than mowing, you can greatly enhance the attractiveness of a lawn throughout the summer.
Fertilizer Is A Must
If nothing else, you should apply fertilizer. It will help thicken the grass by stimulating rhizome development.
Rhizomes, underground stems, spread horizontally with many nodes, each producing a new plant.
The new plants produce thick sod. Fertilizer also gives the grass a deep green color and lush appearance.
Every lawn needs fertilizer, and it should be applied before April. Any commercial lawn fertilizers can be used.
Complete Fertilizers
Complete fertilizers (those containing nitrogen, phosphorus, and potassium) are best.
Apply enough to put two pounds of actual nitrogen on every 1,000 square feet of lawn. Refer to the first number in the fertilizer analysis to figure out application rates.
The number indicates the actual pounds of nitrogen in 100 pounds of fertilizer. Thus, 20 pounds of fertilizer with a 10-8-6 analysis will supply two pounds of nitrogen.
Two Nitrogen Types
Some lawn fertilizers contain slowly available nitrogen sources (such as ureaform). These are satisfactory if they also contain a readily available form of nitrogen.
Slow-Acting Nitrogen
Slow-acting nitrogen alone is likely to be wasted on unwatered lawns since the nitrogen is not released during hot, dry weather.
When applying fertilizers having half of their nitrogen in slowly available form, use four pounds of actual nitrogen per 1,000 sq. ft.
One application in spring should be enough until fall, when another should be made. A fall application is also necessary when a quickly available nitrogen source is used.
In addition, one or two applications of straight nitrogen material, such as ammonium nitrate, should be made during the summer. Apply one pound of nitrogen for every 1,000 square feet of lawn area.
Spring Fertilizer Application
In spring, apply fertilizer after raking and rolling. Use a hopper-type spreader or one of the newer broadcast types.
Uniform distribution is necessary. Otherwise, your lawn will have streaks of various shades of green.
Make Room For New Plants
Rake lawns in early spring to remove leaves, stems, and other accumulated debris.
Use a garden rake. The firm iron prongs will remove excess clippings and make space for new plants which develop from the rhizomes.
When you mow in the spring, removing clippings is a good idea since they do not decay rapidly in cool weather and will accumulate quickly in previously cleaned areas.
Removal Of Clippings
Removal of clippings throughout the year helps reduce disease problems. Disease-producing fungi live as well on dead clippings as on living grass.
Rolling after raking helps to firm the sod, which you loosened with the rake, and smooths the lawn. Do not use a heavy roller.
Rolling Of Lawn Is Prohibited
Do not roll the lawn when the upper inch of soil in a nearby flower bed works into a mud ball.
If the soil is wet or the roller is too heavy, the soil becomes compacted, hindering grass root development and water absorption.
Mow High
After rolling, let the grass grow to a height of 3” to 3” and ½” inches, and then mow it. Start the season with a freshly sharpened and adjusted mower.
The grass can grow long things at the ground level when cut short. Thin sod leaves room for weed seedlings to grow.
Don’t cut the grass shorter than an inch and a half. Tests show root development progressively reduced as the height of the cut is lowered.
Small Root System
Small root systems do not absorb enough water and nutrients to support the vigorous rhizomes and stem needed for a thick turf.
You should expect to mow twice a week in spring. Grasses, especially Kentucky bluegrass, grow most in cool weather when there is lots of moisture in the ground. Unfortunately, there is no way to avoid mowing.
To date, no attractive short-growing grasses have been developed, and no scientist has developed a fertilizer or maintenance program that produces dense, thick turf of good color but little vegetative growth.
Don’t Let Weeds Start
A dense turf provides tough competition to germinating weed seeds. Maintaining a thick sod can cut your weed problem to practically nothing.
But you will need a program that keeps out all weeds because they are likely to take over once they get a start. The idea is to eradicate weeds before they can go to seed.
Hand Digging
Hand digging is still the technique if you have only a few weeds. If weeds are a serious problem, however, you should use chemicals.
Two types are available, those that kill weeds before they are noticed (pre-emergence type) and those that you apply to the weed plants which are obvious (post-emergence type).
Crabgrass Control
The former type is useful, especially for crabgrass control. It is important to apply it before crabgrass germinates, in fall or early spring.
Post-emergence types are used for crabgrass and other weeds. This is most effective when applied to young weed seedlings.
More details on weed control are given in the chart.
Watch For Diseases
Weed control chemicals may temporarily injure the grass. Usually, the injury disappears as new leaves develop. Don’t confuse chemical injury with disease.
Kentucky Bluegrass
The most common disease is the Kentucky bluegrass leaf spot. It occurs in spring and early summer and is most common during cool, wet springs.
Leaves develop small purple to brown spots which spread and completely wrap the base of the leaf or sheath.
When this happens, the leaves turn yellow and finally brown. Crowns, stems, roots, and rhizomes turn brown and rot.
Organic Mercury For Control
Chemicals such as organic mercury can be used for control. Start treatment in late April and continue at two-week intervals until three sprays have been applied.
Other diseases may cause trouble, but their identification is difficult. For example, insects, female dogs, and an overdose of fertilizer may cause symptoms that look like diseases.
A well-managed, vigorous turf is not likely to be as severely damaged by disease as a poorly managed lawn.
Supplement Nature’s Water Supply
Artificial watering is often necessary for the maintenance of green grass. Occasionally even in the spring, watering is desirable.
The main problem with watering is applying enough water in a relatively short time to moisten the soil to a depth of 6” inches.
Rule Of Thumb: Water Supply
A rule of thumb is to apply 1” inch of water to the soil in a 3- to 4-hour period. Then, adjust the nozzles and water pressure to supply the amount of water needed.
A good measure method is to place several coffee tins within the nozzle coverage area.
When the average water height in the cans is an inch, you can be relatively sure that you have applied enough water.
One inch a week will provide average soil moisture needs, except during extremely hot periods.
Rapid and morning applications permit the grass to dry out, which is desirable.
Dry grass is less susceptible to disease than grass kept constantly moist by frequent light watering, which also encourages crabgrass.
Insect Nuisances
Grubs usually are responsible for turf damage caused by insects. The injury-dead patches of sod, which can be lifted in chunks — usually do not show up until summer.
Spring turf treatment with chlordane will grub-proof the lawn for the entire year. Use a one-quarter pound of actual chlordane per 1,000 square feet of lawn and apply directly to the surface.
Other insects, especially the nuisance types such as chiggers, are found in lawns. Again, control is for personal comfort rather than turf betterment.
Reseed Thin Lawns
If your turf is thin but doesn’t have many bare spots larger than a 3”-inch circle, don’t worry about reseeding.
Carrying out the program already described will thicken the turf. However, if there are large bare areas, reseed or replace the poor turf with sod.
Reseeding should be done as early in spring as possible. Sow seed after raking. Use one pound of seed to 1,000 square feet of lawn.
Kentucky bluegrass for sunny areas and creeping red fescue for shade or dry soils are two of the best. Rolling will help press the seed into contact with the soil.
Mowing Of Grass
Mow as soon as existing grass reaches 3” and ½” inches, regardless of the height of the new seedlings. New grass may be injured by the herbicides.
You should know the name of the weed you want to kill before making treatment.
Consult your county agent, local nurseryman, or golf course superintendent for identification. Always follow instructions given on the containers or packages.
44659 by H. R. Kemmerer