Spring has finally sprung. Last week I was scraping ice off of my windshield and next week we may have temperatures in the 80s. I predict a lot of gardening and lawn cleanup this weekend.

There has been an uptick in calls and visits to the Summit Extension office in the last week, and the vast majority of questions have been lawn-related. Most questions were related to hairy bittercress, crabgrass or moss issues.

Hairy bittercress

Hairy bittercress (Cardamine hirsuta) has proved to be a huge problem in landscape beds and lawns this spring. This winter annual usually germinates in August and forms a small rosette that persists over the winter. As soon as the weather warms, the plant sends up stalks with small, white flowers.

A couple of years ago, I would see it in landscape beds, but I am now seeing infestations in well-established lawns. Unfortunately it is currently going to flower in most of the region. According to the University of Florida, one plant can produce up to 5,000 seeds.

Once the seeds are mature, the plant uses a seed dispersal mechanism known as ballochory. When the seed pod is disturbed or reaches maturity the seed pod will split and shoot the seeds in many directions (up to 16 feet). The seeds will lie dormant until late summer, then begin to germinate.

In lawns, the young plants can sometimes be overlooked. It takes only a few ignored plants to produce enough seed to be problematic in the next season.

Removal by hand or mowing is highly recommended before flowering. Don’t place pulled plants in compost piles in case the plants do manage to set seed. Post-emergent, broadleaf herbicides may be effective while the plant is actively growing, before it sets seeds, but it may be too late for this season.

Crabgrass

Crabgrass is the bane of many lawn owners. Smooth crabgrass is an annual weed that will begin to germinate in the spring when the soil temperature in the upper inch of the soil reaches 54 degrees for seven days in a row. Large crabgrass germinates a little later. This year has been somewhat odd in the fact the soil temperature has been inconsistent.

Timing of application of pre-emergent crabgrass preventer is important. If used too early or too late it will be ineffective. One environmental indicator for the right time to apply crabgrass preventer is blooming forsythia, which is currently occurring in most of the region.

For more information on crabgrass preventers, see the resources in the accompanying box. Other management strategies for crabgrass control in lawns is proper mowing and maintaining a vigorous turfgrass stand.

Moss

Another issue that my colleagues and I have noticed over the last couple of years is the increased presence of moss in lawns, which indicates that the grass is weak and has thinned out. There are many reasons for grass to decline, including soil compaction, pH issues, shade and low fertility.

Modifying soil conditions will encourage healthy grass growth and discourage moss. If the area is shaded, pruning trees and shrubs will allow more light and air circulation.

A common mistake is adding lime, which will raise the pH of soil; if you already have a high pH, adding lime will make the problem worse. A soil test can help you determine if there is a pH issue.

If your soil is compacted, core aerating may help improve drainage. Moss issues can also occur when the grass isn’t receiving enough nitrogen. Adjusting nitrogen application may helpful. Excessive, low mowing may encourage moss growth, so raising mower height is recommended.

Raking the moss and reseeding grass is another strategy, but if the underlying problems that caused the moss to grow in the first place are not solved, it may return quickly.

Jacqueline Kowalski is the Summit County Agriculture and Natural Resources Extension Educator for the Ohio State University. For questions on local foods, food production or other garden-related questions, contact her at kowalski.124@osu.edu or 330-928-4769 ext. 2456. The Extension Master Gardener Volunteer Hotline is open. For answers to your gardening questions, call 330-928-4769, select option 3 or extension 2481 or 2482, Tuesday mornings 9 a.m to 12 p.m.