Fielding Questions: Pine needles dropping, clover lawns, powdery coating on monarda
Read on as Don Kinzler explains how pine trees shed needles, the benefits of clover lawns and preventing powdery mildew.
Q: I'm attaching a picture of the Tannenbaum Mugo Pine tree in my front yard. In October, when the photo was taken, the needles started to turn yellow and the branches dropped a lot of needles. Do you know what could be wrong? – Ross M.
A: Good news; this pattern of needle drop is normal. Pines hold their needles for three-to-five years before the older, inner needles cycle out and are shed. These are the needles that end up on the forest floor.
As long as it’s the older needles inside the pine that are shedding, there’s nothing to worry about. If needles turn brown on the outer perimeter of the pine, then there’s cause for concern.
Older pine needles normally cycle out, turn color, and drop sometime between August and October. This natural shedding is more visible on young pines that we tend to observe more closely than large, older pines, although it occurs on both.
Q: After the problems we’ve had with very little rain and more disease trouble in lawns, would a clover lawn be a better alternative? Will it overtake and crowd out quack grass? Please say yes. I admit it would take some getting used to but I’m tired of just trying to keep my grass alive these last two years, let alone have it look decent. – Ona V.
A: In the 1940’s and ‘50s, lawns that included clover were considered upscale. In the decades following, as lawn herbicides became common, golf course-looking lawns with pure stands of grass became the trend. We’ve come full circle, and we’re once again realizing the benefits of clover lawns.
There are great advantages to overseeding a lawn with white Dutch clover. Clover’s deep roots make it drought tolerant, remaining green after many lawngrass types have turned brown, requiring much less water.
Clover lawns don’t require fertilizer, because clover is a legume, which manufactures nitrogen and adds this fertilizer element into the soil. Clover crowds out weeds, and eliminates herbicide applications. Clover might not totally eliminate quackgrass in a lawn, but it will greatly diminish it.
Clover lawns develop and spread without high maintenance. Where clover is blended into existing lawngrass, the clover provides fertility that helps grass stay healthy.
A possible downside of a lawn that’s strictly clover is its inability to withstand heavy foot traffic, but blending clover and grass together increases the ability. With a clover lawn, you can skip aerating and power raking, because clover’s deep roots penetrate the soil, eliminating compaction.
Clover in a lawn also attracts pollinators, and when pollinators increase, fruit and vegetable production also increases.
With all the benefits, it’s no wonder clover lawns are becoming popular. The best type for lawns is white Dutch clover, which is becoming increasingly available and can be overseeded in lawns in fall or spring.
Q: Our monarda is very vibrant and beautiful in the spring, and flowers are a beautiful pink color. In summer, the foliage develops a powdered appearance. Is that natural? – Susan G.
A: Monarda is a beautiful perennial and well worth adding to any perennial garden. Many cultivars, though, are susceptible to a fungus disease called powdery mildew, which can reduce the vigor of the plants, and make the leaves look unsightly as they develop a grayish white coating.
Control of powdery mildew is all about prevention, because once the white coating appears, it can’t be reversed or washed off. For new plants, look for cultivars that indicate mildew resistance. For established plants, avoid getting water on the leaves when sprinkling and apply fungicides containing the active ingredient chlorothalonil while the leaves are still disease-free.
If you have a gardening or lawn care question, email Don Kinzler, NDSU Extension-Cass County, at firstname.lastname@example.org . Questions with broad appeal may be published, so please include your name, city and state for appropriate advice.