Mulching leaves? - Ask Extension
Hello,
I left a voicemail with this question but I’m not sure it went through. I recently had a landscaping company aerate and over-seed my lawn...
Knowledgebase
Mulching leaves? #888873
Asked October 28, 2024, 9:30 AM EDT
Hello,
I left a voicemail with this question but I’m not sure it went through. I recently had a landscaping company aerate and over-seed my lawn. Now that leaves are falling I was planning on using my lawnmower to mulch the sulfur maple leaves into my lawn. I also have vegetable garden beds that I was considering covering with leaves, but was wondering whether I should mulch them first or not.
The landscaping company owner advised against mulching the leaves so as not to harm moth and butterfly eggs. But I need to remove them from the lawn anyway to allow sun and water to reach it so I’m confused about how that would work.
Overall, what do you advise for making the most out of my abundant silver maple leaves in terms of my lawn and garden bed health?
Hennepin County Minnesota
Expert Response
Thank you for writing.
I have exactly the same situation in my yard. The silver maple is a pretty and pretty messy tree.
Do NOT mulch with a raking blade on your mower because it will tear the new grass out of the ground.
Leaves decay naturally. Most of the winter habitat is in garden beds, bushes that are densely covered with leaves. The layer of leaves over grass is less important.
Gently hand rake the lawn to move leaves to those areas. You might use a blower as well.
I rake as they fall, about once a week. I think next week will be first.
Be sure to water your lawn up to mid Dec.
Right now your mower should be set at about 4 inches, the final cut in November can be 2.5
https://xerces.org/blog/leave-the-leaves
I have exactly the same situation in my yard. The silver maple is a pretty and pretty messy tree.
Do NOT mulch with a raking blade on your mower because it will tear the new grass out of the ground.
Leaves decay naturally. Most of the winter habitat is in garden beds, bushes that are densely covered with leaves. The layer of leaves over grass is less important.
Gently hand rake the lawn to move leaves to those areas. You might use a blower as well.
I rake as they fall, about once a week. I think next week will be first.
Be sure to water your lawn up to mid Dec.
Right now your mower should be set at about 4 inches, the final cut in November can be 2.5
https://xerces.org/blog/leave-the-leaves
Thanks Steve. I don’t have a raking blade. By “mulching” leaves I meant just running over them with my regular mower at around 3” (my grass is mostly brown so not much to cut back there right now sadly).
The Leave the Leaves concept makes sense - it just seems to be a different approach than what's recommended here:
I have stopped watering my lawn for about a month now after I had it aerated and overseeded. Do you still recommend watering it?
Thank you for writing back.
I enclose a picture of a mulching blade. Thank you for clarifying.
Here is a lawn care calendar. https://extension.umn.edu/planting-and-growing-guides/lawn-care-calendar It calls for watering through the end of October but this should be extended this year because it has been hot and dry. Here is some University thought on this year. https://extension.umn.edu/yard-and-garden-news/should-you-water-your-lawn-winter
Your lawn has two kinds of stress. 1. The drought stress on the older grass. 2. The new seed which is trying to set roots.
The ground will not freeze hard until mid December. Current ground temps are still about 50 degrees. This is the Soll temp at the St. Paul Campus. http://160.94.1.5/?command=TableDisplay&table=SevenAM&records=7
This is the watering schedule after seeding. https://extension.umn.edu/lawn-care/seeding-and-sodding-home-lawns#:~:text=Lightly%20rake%20allowing%20about%2010,to%204%20times%20per%20day.
With regard to your comment on mulching, I agree with the U on raking to prevent lawn smothering. However your situation is a bit different in that you have incompletely rooted grass seeds which are susceptible to being mechanically disrupted by raking or mowing. That is the reason for the gentle frequent raking schedule that I spoke of for the LAWN. The primary benefit of fall leaves to lawn soil is adding organic material to loosen the soil structure. Leaves are a poor fertilizer. https://gardenprofessors.com/leaves-for-lawn-fertilizer/
The garden beds and the planted areas under the trees can handle much heavier lawn debris, hosta and trees have deep roots. Shrubs never get buried. Even so, a silver maple will make a lot of leaves and you will have to bag some and send them away.
I enclose a picture of a mulching blade. Thank you for clarifying.
Here is a lawn care calendar. https://extension.umn.edu/planting-and-growing-guides/lawn-care-calendar It calls for watering through the end of October but this should be extended this year because it has been hot and dry. Here is some University thought on this year. https://extension.umn.edu/yard-and-garden-news/should-you-water-your-lawn-winter
Your lawn has two kinds of stress. 1. The drought stress on the older grass. 2. The new seed which is trying to set roots.
The ground will not freeze hard until mid December. Current ground temps are still about 50 degrees. This is the Soll temp at the St. Paul Campus. http://160.94.1.5/?command=TableDisplay&table=SevenAM&records=7
This is the watering schedule after seeding. https://extension.umn.edu/lawn-care/seeding-and-sodding-home-lawns#:~:text=Lightly%20rake%20allowing%20about%2010,to%204%20times%20per%20day.
With regard to your comment on mulching, I agree with the U on raking to prevent lawn smothering. However your situation is a bit different in that you have incompletely rooted grass seeds which are susceptible to being mechanically disrupted by raking or mowing. That is the reason for the gentle frequent raking schedule that I spoke of for the LAWN. The primary benefit of fall leaves to lawn soil is adding organic material to loosen the soil structure. Leaves are a poor fertilizer. https://gardenprofessors.com/leaves-for-lawn-fertilizer/
The garden beds and the planted areas under the trees can handle much heavier lawn debris, hosta and trees have deep roots. Shrubs never get buried. Even so, a silver maple will make a lot of leaves and you will have to bag some and send them away.
I was thinking about your lawn this evening. Could you shoot a close up picture of an area of turf where it is possible to see the new grass seed?
I tired taking a few photos but it’s hard to see any seed as far as I can tell…
I’m also attaching the veggie patch and some raised beds which it sounds like I should cover with leaves. Perennials get covered and annuals remove, right?
Hi Sami,
It was a cloudy day, I can't read the direction of your photos or shade patterns.
The ground is cracked and dry. I do not see germinating grass seed. My suggestion would be to get a mixture of fescues from a good garden store and overseed again by hand in April.
You do not have enough leaves on the grass now to worry about. The large circular of dead grass near your dog is worrisome. It could be Japanese beetle borers or it could be dog urine or it could simply be dry. Write me in the spring and we can go from its spring appearance.
Your garden boxes are under the eaves--depending on the directions, this could cause shade to be excessive. The eave could obstruct rainfall on the box.
I bag my weeds and send them away (to get rid of the seeds) and compost my leaves. Your situation may not allow that.
It was a cloudy day, I can't read the direction of your photos or shade patterns.
The ground is cracked and dry. I do not see germinating grass seed. My suggestion would be to get a mixture of fescues from a good garden store and overseed again by hand in April.
You do not have enough leaves on the grass now to worry about. The large circular of dead grass near your dog is worrisome. It could be Japanese beetle borers or it could be dog urine or it could simply be dry. Write me in the spring and we can go from its spring appearance.
Your garden boxes are under the eaves--depending on the directions, this could cause shade to be excessive. The eave could obstruct rainfall on the box.
I bag my weeds and send them away (to get rid of the seeds) and compost my leaves. Your situation may not allow that.
