homepage logo

Schmidt: September the best month for lawn improvments

By Staff | Sep 5, 2014

Regardless of your lawn preference, NOW is the best time to improve your lawn. Consider the following: Fill in bare spots. Now through mid-September is the best time of the year to sow grass or lay sod. The ground is still warm and the seeds will germinate quickly. As a bonus, weeds are less likely to germinate in lawns established in fall compared to lawns established in spring. Choose a quality seed mix with a variety of grasses.

Most seed mixes will include cultivars of Kentucky bluegrass, fine/red fescues, and perennial ryegrass. Kentucky bluegrass is a hardy grass that is recommended for sunny areas. The fine/red fescues are best for shade. Perennial ryegrass is especially useful since it germinates rapidly and stabilizes the soil while the other lawn grasses emerge. If you plan on using sod, you’ll be pleased that it grows actively in fall and will quickly “knit” into the ground.

Fertilize the lawn. Fall is the most important time to fertilize your lawn. Lawns grow vigorously and will develop most of their roots this time of year. If you fertilize your lawn only once a year, do so in September. Fertilizer has three major components: nitrogen, phosphate and potash. Nitrogen is most important for turf growth-look for a fertilizer that has more than 20 percent nitrogen. Select a fertilizer with slow-release nitrogen. This will gradually feed the grass until the ground freezes. As for the other major nutrients, phosphate is least important because it is already abundant in most soils. Potash will help the lawn become hardy for winter – look for a fertilizer that is at least 10 percent potash. Kill broadleaf weeds. Mid- to late-September is the best time to kill broadleaf weeds, including dandelion, creeping charlie, thistles and clover. As days get shorter, the weeds will begin channeling their nutrients down into their roots to prepare for winter. This is great, because a herbicide sprayed on a weed at this time will naturally be channeled down into the weed’s root system, killing the entire plant.

Aerate. If your soil is hard and compacted, fall is the best time to aerate it. Aerated lawns will respond with vigorous root growth until the ground freezes. Many persons overseed immediately after aeration. If overseeding, do this by mid-September. Dethatch. Lawns with thatch layers exceeding one-half inch will benefit from a power raking. This is best done in September.

Planting Trees in Fall

Fall can be a great time to plant trees. Temperatures cool off, thereby reducing heat stress and transplanting shock to the trees. The soil is warm and not too wet, making it easy to work with. Lastly, there can be some great bargains in the fall as some nurseries sell out their stock before winter sets in. The cold hard reality is that winter is coming and we want to give our trees as much time as possible to get well rooted before the bitter cold weather arrives. Ideally, give your trees at least four weeks of time to grow new roots and begin their recovery from transplanting.

Tree roots will grow as long as temperatures stay in the 40s. Soils will stay this warm until early October in the northwest corner of the state and until late October in the warmest regions. Therefore, try to get your trees planted by mid-September in the northwest part of the state and late September to early October in the warmest parts of the state.

When planting trees in fall, the quality of the nursery where you purchase the trees makes a big difference. These trees have been sitting in containers or in burlap-covered balls all summer long. A quality nursery can take proper care of its trees over summer, but a not-so-quality nursery could have caused severe stress to its planting stock over this time. Be cautious.

Some tree species are more sensitive to fall planting than others. Evergreens in general are sensitive. Their needles will be exposed to drying winds all winter, making these plants especially subject to injury. Try to get your evergreens planted by the end of September. This is especially true for arborvitae, a broad-needled evergreen. Among the most sensitive leafy trees are red maple, birch, poplar, cherry, plum, willow and many oaks. These trees generally have a less fibrous root system than others. Make sure you get a good bargain before planting these trees and try to get a one-year guarantee from the nursery. Hackberry is reported to transplant better in fall than in spring.

Avoid planting large trees in fall. Big trees may lose 75 percent or more of their feeding roots in the transplanting process and suffer from severe transplanting shock. Plant them in spring when they have a full growing season to recover before they face their first winter. Water your newly planted trees regularly until the ground freezes. Most trees need one inch of water per week. This is about 10 gallons of water per inch of trunk diameter at breast height. Make sure you are watering several inches deep. Put some wood mulch around the tree to conserve moisture and protect the root system from extreme soil temperatures. Extreme temperatures cause repeated freezing and thawing of the soil, which can cause the soil to shift and damage the roots. Wrap leafy trees or place a white tree guard around the trunk to protect the young plants from sunscald and wildlife.

For more information on either topics you may contact the NDSU Extension Service Pierce County office by calling 776-6234 ext. 5 or by email at yolanda.schmidt@ndsu.edu.

Please Enter Your Facebook App ID. Required for FB Comments. Click here for FB Comments Settings page