When some think of spring, they think “spring cleaning.” The stuff that has gathered all winter now can be organized or ushered out the door.
Spring cleaning is for outdoor spaces as well. It is time to pick up what the wind has brought into the yard, discover gardening tools that were not properly put away and also, clean out garden and flower beds.
Linn County Master Gardener Lisa Slattery has tips for chores that will help you get ahead of lawn and garden season.
Q: When is the proper time to apply pre-emergent herbicide, fertilizer and broad-leaved herbicide to my lawn?
A: Crab grass is a self-re-seeder so it can be invasive if not properly controlled. However you can get a handle on it if your timing of applying a pre-emergent herbicide application is correct. Master gardeners typically tell you to “apply it when the Forsythia blooms start to drop.”
Crab grass seeds begin to germinate when soil temperatures reach about 55 degrees to 60 degrees and continue to germinate for several weeks. That’s why it’s extremely important to get your pre-emergent in place before those seeds germinate. Proper time is early to mid-April in southern Iowa, mid-April to May 1 in central Iowa and late April to early May in Northern Iowa.
As we all know, weather varies widely from year to year. Last spring we experienced warm temperatures early, ISU Extension says we are about one week behind with cooler temps this year. So pre-emergent applications need to be tweaked just a bit to correspond with our changing weather. This year, applying the herbicide a week later in the recommended time frame will probably be correct. But keep your eye on Mother Nature and mind the beautiful yellow blooms of the forsythia, as well as redbud trees beginning to bloom, to take your cue from the weather. Crab grass seeds typically germinate shortly thereafter.
Spring also is the time to fertilize your lawn. If you fertilized your lawn last fall, it will green up quicker this spring. Most of our lawns in Iowa are cool season grasses that benefit more from fall fertilization applications, but if you are going to fertilize in spring, April or May is the proper time frame. Don’t fertilize cool season grasses in June, July and August. When fertilizing, don’t apply more than one pound of actual nitrogen per 1,000 square foot area in one application. Also if you choose a granular product, make sure that you sweep or blow any residual fertilizer off driveways, streets and sidewalks back into your lawn to help prevent excessive fertilizer run off into waterways.
The best method to eradicate broad-leaved weeds from lawns is to hand dig and pull. However, if your broad-leaved weed problem is widespread and hand digging isn’t practical, apply a broad-leaved herbicide in fall. That’s the time when weeds are transporting food from their foliage to their roots in preparation for winter. That means fall is the time when weeds will absorb most of an herbicide to more effectively destroy it at the roots.
When using pre-emergents, fertilizers and herbicides always follow label directions for proper applications.
— Linn County Master Gardeners Creative Gardening Series: Rita Minard, “Clematis for Iowa Gardens” 6:30 to 8:30 p.m. Tuesday at Kirkwood Community College, Cedar Hall Room 234, 6301 Kirkwood Blvd. SW. Tips on how to grow, prune and display these plants in unique and fun ways. Minard is a Polk County master gardener, a member of the American Clematis Society and treasurer of the advisory council of the Des Moines Botanical Center. Free.
— Container Gardens, 6:30 to 7:30 p.m. Thursday at the Ely Public Library, 1595 Dows St., Ely. Container gardens do not have to be three geranium, asparagus fern and vinca vines. Come see what can be done with your containers. Master Gardener Deb Walser’s own containers will be featured along with planting instructions. Free.
— Oliver & Ava’s River Raft Adventure Exhibit Grand Opening, 10 a.m. to 4 p.m. Saturday at Wickiup Hill Learning Center in Toddville. The expanded exhibit project promotes youth education of critical natural resources, renewable energy and sustainable communities, provides a hub for family activities and lifelong learning opportunities and education about the Cedar River.
Michelle Kenyon Brown is community ag programs manager for Linn County Extension & Outreach. Send questions to “From the Ground Up” to: firstname.lastname@example.org