Rehabilitate Lawn - Ask Extension
Good evening,
Several years ago, you offered me invaluable information on rehabilitating my lawn from scratch. The results were fabulous, but it di...
Knowledgebase
Rehabilitate Lawn #869671
Asked May 22, 2024, 5:56 PM EDT
Good evening,
Several years ago, you offered me invaluable information on rehabilitating my lawn from scratch. The results were fabulous, but it didn't last (due to my lack of sufficient effort).
Given that we are almost at Summer, is there any proven method to (experimentally) rehabilitate my grass? That is, remove weeds, strengthen (and overseed grass), some moss issues in certain areas.
I can no longer start "from scratch"; I am not killing everything, tilling the soil, etc.
Thank you!
Montgomery County Maryland
Expert Response
Do you have a cool-season lawn (fescue) or a warm-season lawn (zoysia)? The timing or rehabilitation efforts will depend on which you have. Based on the prior questions we can see, we presume it's fescue.
Tall fescue is best seeded in late summer to early autumn (around late August or so into early October). Seeding now, this close to summer, will not tend to produce good results. If the soil is compacted from regular use of the lawn, you may want to core-aerate just prior to seeding, which will both reduce some of the compaction as well as boosting seed-to-soil contact, which improves germination rates. Moss might indicate areas of poorer drainage that is often tied to compaction, and might also imply that the soil in those areas is too acidic for the lawn to prosper. The only way to be certain, though, is with a laboratory soil test. (Home test kits are harder to read and less accurate or detailed.) This will not only determine if applying any lime before seeding is recommended, but also if any particular nutrients could use supplementation beyond the normal lawn fertilization dosages.
Montgomery County regulates lawn herbicide use, but the first step to managing weeds is proper plant identification. Feel free to send us photos of any weeds you cannot ID using the information on our lawn weeds pages. Different weed species may require different approaches to either removal or discouraging their reappearance in the future. Organic herbicides, which the county does permit, will only tend to kill above-ground growth, not roots, so removal of any harder-to-kill weeds will take more effort (repeat treatments) and/or digging out what you can manually.
More information about lawn care and maintenance can be found on the linked pages. Using recommended turfgrass cultivars (where possible) will also help build-up a disease-resistant lawn more tolerant of stress like summer heat and drought. As we move into hotter and drier weather, irrigate only when needed (extra leaf wetness encourages disease) by feeling the soil about four inches deep and watering only once it becomes somewhat dry to the touch at that depth. It's okay if some of the lawn goes summer-dormant and looks a little brown; that's normal for fescue since it only actively grows in cool weather.
Miri
Tall fescue is best seeded in late summer to early autumn (around late August or so into early October). Seeding now, this close to summer, will not tend to produce good results. If the soil is compacted from regular use of the lawn, you may want to core-aerate just prior to seeding, which will both reduce some of the compaction as well as boosting seed-to-soil contact, which improves germination rates. Moss might indicate areas of poorer drainage that is often tied to compaction, and might also imply that the soil in those areas is too acidic for the lawn to prosper. The only way to be certain, though, is with a laboratory soil test. (Home test kits are harder to read and less accurate or detailed.) This will not only determine if applying any lime before seeding is recommended, but also if any particular nutrients could use supplementation beyond the normal lawn fertilization dosages.
Montgomery County regulates lawn herbicide use, but the first step to managing weeds is proper plant identification. Feel free to send us photos of any weeds you cannot ID using the information on our lawn weeds pages. Different weed species may require different approaches to either removal or discouraging their reappearance in the future. Organic herbicides, which the county does permit, will only tend to kill above-ground growth, not roots, so removal of any harder-to-kill weeds will take more effort (repeat treatments) and/or digging out what you can manually.
More information about lawn care and maintenance can be found on the linked pages. Using recommended turfgrass cultivars (where possible) will also help build-up a disease-resistant lawn more tolerant of stress like summer heat and drought. As we move into hotter and drier weather, irrigate only when needed (extra leaf wetness encourages disease) by feeling the soil about four inches deep and watering only once it becomes somewhat dry to the touch at that depth. It's okay if some of the lawn goes summer-dormant and looks a little brown; that's normal for fescue since it only actively grows in cool weather.
Miri
