Kermit the Frog once crooned "It's Not Easy Being Green." If you have a lawn, you can relate: It's not easy keeping things green. If you lack the time, knowledge, or willpower to do that, it's time to call in the pros, but you'll still need to do some work. Here's how to plot a course.

To help you find a lawn service company, nonprofit consumer group Twin Cities Consumers' Checkbook magazine and Checkbook.org surveyed consumers (primarily its members and Consumer Reports subscribers) for their ratings. Through a special arrangement, Star Tribune readers can access Checkbook's ratings of local lawn care services for free through Aug. 5 at Checkbook.org/StarTribune/lawn.

Checkbook's ratings reveal that the lawn care field produces substantial numbers of dissatisfied customers. Some companies failed to get "superior" overall ratings from even half of their surveyed customers. Most complaints relate to poor work or poor results. Fortunately, several area companies satisfy almost all their customers.

Invite several companies to inspect your lawn and propose programs and prices. Get companies to commit to meeting your expectations and to an overall cost. For average-size lawns, price differences of more than $300 per year are common. It's best to meet with representatives in person. This is a good way to size them up and get answers to any questions.

Help the company propose a program that will satisfy you by explaining your tolerance for weeds, thin spots, and other lawn defects; what you envision as the end result of the treatments; how soon you except the lawn to reach an acceptable condition; how much work you are willing to take upon yourself; how strong your concerns are regarding the use of chemical fertilizers and pesticides; and what kinds of notification and other precautions against possible pesticide risk you will expect.

Because different companies will propose different combinations of treatments, you won't be able to compare proposals and prices on the basis of the tasks that will be performed. Rather, you'll have to describe the level of quality you want and any special constraints you wish to impose and get prices for the service each company recommends to meet your objectives.

Your choice of a company and a lawn care program will have to be made as a single decision because you'll have to choose a program that a company agrees is appropriate and efficiently fits into its work routines. You will also probably want a company's help in designing your program, but be aware that the Checkbook's shoppers find most companies' sales staff aren't very informed and their advice should be received with skepticism.

Keep in mind that more treatment — at least in the short term — is not necessarily better treatment. Any company can produce a quick flash of green growth with quick-release fertilizer that weakens your lawn's root systems. A company that treats your entire lawn with herbicides and pesticides may be less effective than one that targets limited areas and specific problems — and subjects you and your surroundings to the least possible chemical exposure.

Ask the company you select to guarantee in writing that it will refund your money for an entire year if you are not satisfied that it has met its commitments; we found many companies will offer this guarantee.

Whatever professional lawn treatments you get, how and when to mow the lawn is key. Make sure you don't mow too short. Most grasses should not be cut below a height of about two-and-a-half to three inches. Mow frequently enough so that no more than one-third of the leaf is cut off at any one time. Mower blades should be sharp, so that the cut ends of grass leaves aren't torn, which makes them brown and vulnerable to pest attack. Mow when grass is dry. Leave clippings on the lawn so they can return nutrients to the soil; but if the grass grows too long between mowings, you might have to spread clippings out so they don't form areas of matting on top of the lawn.

Twin Cities Consumers' Checkbook is a nonprofit organization supported by consumers and take no money from the service providers they evaluate.