Turf Care Frequently Asked Questions

Yellow or brown grass may be caused by drought stress, overwatering, poor drainage, nutrient deficiencies, incorrect mowing, insects, fungal disease, or seasonal dormancy. The shape, position, and time at which the discoloration occurs can assist in working out the reason. For instance, brown patch typically strikes Fescue when the weather is warm and humid, whereas large patch can affect warm-season grasses like Zoysia and Bermuda when the conditions are cooler and wetter. Since a number of lawn problems show similar symptoms, the best approach for finding the right treatment is to have a professional carry out an inspection.

These products address different lawn problems:

• An herbicide controls unwanted plants and weeds.
• A fungicide helps prevent or manage fungal lawn diseases.
• An insecticide controls insects that may damage turf, roots, or landscape plants.

The choice of product should be based on the problem, the type of grass, the weather conditions, and the time of year; using a product without first properly identifying the problem may result in wasting money or possibly damaging the desired turf.

The timing will vary depending on the type of weed and the herbicide used. Pre-emergent herbicides must be applied before the weed seeds in question have developed, whereas post-emergent herbicides are used on weeds that are already growing. In West Tennessee, spring applications of pre-emergent herbicides for crabgrass are usually made in late February or early March, that is, before soil temperatures stay close to 55°F. Treatments in the fall are effective at preventing a number of winter weeds. The timing of post-emergent applications is based on the growth of the weeds, the temperature, the type of grass, and the instructions for the product—not just on a fixed calendar date.

A pre-emergent herbicide forms a protective layer which prevents the target weed seedlings that are germinating from growing into mature plants and has to be applied before the weeds become established. A post-emergent herbicide is used to deal with weeds which have already come up and are growing actively. It is possible for a full weed control programme to make use of both types of herbicide at various stages during the year.

No, that is generally the case. The majority of pre-emergent herbicides are designed to stop specific weeds from growing rather than to get rid of weeds that are already established. Weeds that are already there usually need the right kind of post-emergent treatment. Although a few products offer both pre-emergent and early post-emergent control, the treatment still has to be chosen according to the particular type of weed and grass.

Fungicide should be used in cases where a fungal disease has been identified or when there is a recurring disease issue which needs to be treated preventively. Symptoms such as circular or irregular brown patches, discolored edges, leaf lesions, and areas that tend to worsen under specific weather conditions could be signs of disease. Yet drought, insects, pet urine, nutrient deficiencies, and damage from mowing can all appear similar. Fungicides are most effective when the disease, the time of application, and the product chosen are properly matched.

Insecticide should be used either when a pest which is causing damage has been spotted or when a preventive treatment is appropriate due to the pest’s life cycle and the lawn’s history. Indications of such damage may be thinning grass, uneven brown patches, blades that have been eaten through, loose sections of turf, or something visible relating to the insects. Since insect damage can be similar to that caused by drought or disease, it is important to identify the pest before carrying out treatment.

There is no one schedule that applies to all types of property. The frequency with which treatment is carried out will vary according to the kind of grass, the presence of weeds, the level of disease and insect problems, the soil conditions, the weather, and the products employed. Rather than depending on a single spraying, most programmes for a healthy lawn involve a series of applications at carefully chosen times during the growing season.

The length of time depends on the type of treatment; in some cases the weeds start to curl or change colour within a few days, whereas in other instances it may take a few weeks or an extra application. It is possible that preventative products are having an effect even if there is no obvious change to sight. Recovery of the lawn following damage caused by disease or insects can take longer since the grass has to grow new shoots.