With spring gardening season right around the corner, lawn questions have been rolling into the Home & Garden Information Center (HGIC). Here I’ll address some of the most common questions about weeds and overseeding.
Dealing with Winter Weeds
In late winter/early spring, we typically see winter annual weeds in thin, under-fertilized, wet, or shady areas. These weeds germinated in the fall and will die as the weather warms up later in the spring. In my observations, this has not been a particularly bad year for winter annuals. They are favored by wet, mild winters and I think we had just enough “bitter cold” in January and a fairly dry stretch through December and January to reduce populations.
Typical winter annual weeds include chickweed, henbit, purple deadnettle, and shepherd’s purse. Options to address these winter annual weeds include hand pulling, spot spraying with a broadleaf herbicide, or waiting until they die once weather climbs to the 60’s and 70’s on a regular basis. For perennial weeds like dandelion which will start to re-emerge later this month, hand-pulling or spot spraying are the best methods for control.
Warm early October weather has extended the “overseeding window” for fall lawn care. While the first week in October is usually the traditional cutoff for establishing new lawns or rejuvenating existing lawns, the warm early October weather has extended the window by 1-2 weeks.
You can read my September blog post for more information on overseeding and you can still do it, but this follow-up post will deal more with a question that has been coming into the Home & Garden Information Center as of late: “I established a new lawn (or overseeded) in September and some weeds are starting to come up — now what?” Continue reading →
Late August through September is usually a good time to transplant, divide and plant perennials such as daylily, liriope (photo left), and echinacea. Be sure to keep them well watered during dry periods.
Annuals and perennials, like yarrow and salvia, may have grown spindly and are not flowering well. Cut them back to encourage re-bloom. Deadhead the spent blooms of annuals like zinnias and marigolds. This will encourage them to continue blooming more vigorously.
Plant hardy mums for fall color this month so they will become well established prior to the winter.
In dry periods grasses go dormant but recover when rain returns. Newly seeded or sodded lawns may actually be dead and will need to be reseeded.
Mid-August through mid-October is the best time to start new lawns and renovate or overseed existing lawns. We recommend a turf-type tall fescue cultivar at a rate of 4 lbs. of seed per 1,000 sq. ft. of area for overseeding, or 8 lbs. per 1000 sq. ft. for new lawns.
If your lawn area contains more than 50% weeds, consider a total lawn renovation. Newly seeded turf must be watered regularly. See Starting a New Lawn.
You may notice the European hornet stripping the bark off shrubs (especially lilac) and trees. This stripping of the bark is usually minor and does no real harm to a shrub or tree. The European hornet is a large yellow and brown hornet (photo) that nests in cavities in trees, stumps, wood piles, sheds, etc. and feeds on insects. Unlike most other wasps and hornets this one is a night flyer.
Do not spray pesticides in your garden unless you’ve observed a particularly serious pest and the damage caused by the pest. Follow all label directions. Always select the shortest residual, least toxic insecticide to avoid killing beneficial insects.
Avoid mosquito and midge problems by turning over any pots, lids or saucers that might collect water and create a breeding site. Also check clogged house gutters another favorite breeding place for mosquitoes and midges. Many people use corrugated drain pipe attached to downspouts to help move water away from their homes. The corrugations hold water and are a prime place for tiger mosquitoes to breed. To avoid the problem, use a smooth drain pipe or securely attach the corrugated drain pipe to the downspout and cover the open end with a piece of pantyhose secured with a rubber band. This will keep adult female mosquitoes and midges out of the drain pipe.