Lawn seeding

Question: Hello. Now that winter is (basically) over, I finally raked up my (small) backyard that we disturbed to put in some flagstone back in the Fall. In leveling the ground and cleaning up the leaves, stones leftover from the pea gravel we used to stabilize the flagstone got strewn around and into the soil. We also have two large bald cypresses that shed leaves and seed pods prolifically in the fall that have mixed into the soil. I wanted to know if it's at all possible to seed grass at this point, what with the stones and even the bald cypress seed pods all over?  I attached a picture of the yard in case you need to see it. Thanks! Andrew

responder: The Question Asker Replied March 18, 2023, 5:22 PM EDT
response: Hello. Now that winter is (basically) over, I finally raked up my (small) backyard that we disturbed to put in some flagstone back in the Fall. In leveling the ground and cleaning up the leaves, stones leftover from the pea gravel we used to stabilize the flagstone got strewn around and into the soil. We also have two large bald cypresses that shed leaves and seed pods prolifically in the fall that have mixed into the soil.

I wanted to know if it's at all possible to seed grass at this point, what with the stones and even the bald cypress seed pods all over?

I attached a picture of the yard in case you need to see it.

Thanks!
Andrew

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied March 20, 2023, 12:55 PM EDT
response: Hi Andrew,  It's probably fine to use as-is since the organic debris (the Baldcypress pods and shed leaves) will decay and add organic matter to the soil to the benefit of plant roots. The inorganic debris (the pea gravel) doesn't appear to be too abundant and so probably won't have much impact on soil drainage or moisture retention if left alone. If in doubt about soil quality, especially if you need to alleviate some compaction from stepping on the soil to lay the pavers, then you can lightly rake-in some compost as a topdressing before seeding or laying sod. Leafgro is a commonly-used locally-made municipal compost that should be fine. An inch or two should be plenty to layer on and then gently incorporate into the surface layer of soil.  If this site is partly or mostly shaded during summer due to the tree canopies, we recommend you consider a lawn alternative instead, since turfgrass will struggle long-term if not receiving enough direct sun. One option, especially if you prefer the look of lawn but don't need to rely on it to tolerate regular foot traffic, is one or more species of sedge (botanical name Carex). The linked page is a very recent publication of trial study results from a relatively nearby public native plant garden that studies the suitability of various native species for garden use. It can be very useful in helping a gardener decide which of the myriad species of native Carex to try based on site conditions (dry soil, moist soil, etc.). While a tolerance to mowing was part of the trial, mowing is not necessary for Carex to thrive, and often the plants look their best without it.  If you need the area to withstand regular foot or pet/child traffic, though, then turfgrass may be the best bet after all, at least among living groundcovers. Our lawn care and maintenance pages can help guide you with regard to what types of turf to choose, when to overseed and fertilize, and other practices that help boost grass performance over the long term.  Miri

responder: The Question Asker Replied March 20, 2023, 1:22 PM EDT
response: Hi Miri, Thanks so much for your answer! Super thorough. I've been thinking about how to incorporate a sedge, but I'm not entirely certain. I'm hoping to have at least moderate foot traffic in the yard and will probably only mow every 2-3 months to let the carex grow. Was foot traffic taken into consideration in the study? We are in pretty shady conditions during the late spring/summer, however, so I'm wondering how well the sedge will be able to thrive. Does that really just depend on the type? Thanks again!AndrewOn Mon, Mar 20, 2023 at 12:56 PM Ask Extension <<personal data hidden>> wrote:

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied March 20, 2023, 3:29 PM EDT
response: No, foot traffic wasn't included in the Mt. Cuba study as far as we recall, though species well-suited to either compacted soils or those skewing wet might be good candidates. (Not necessarily because of the moisture levels outright in this case, but because of the tolerance to the reduced oxygen levels wet soils share with compacted soils. Compacted soils do drain more poorly, though, so that tolerance also helps for simple wetness adaptability.)  Most Carex don't grow very tall (though they do get taller than grass mown to the recommended four-inch height), so mowing to restrain growth isn't necessarily needed, though you can do it for aesthetics if you prefer for the species tested that responded well. Otherwise, Dwarf Mondo Grass (Ophiopogon japonicus 'Nanus' and one or two other varietites) stays quite short at maybe 3-4 inches max, so mowing in that case would not be needed. (Nor would it really accomplish much either.) If the foot traffic follows a certain path, though, then maybe that could just be mulched with wood chips or bark mulch and Carex used over the rest.  Yes, with the dozens (over a hundred, really) of sedge species found in Maryland, plus the handful of non-native selections also, tolerance to sun and shade does vary somewhat. We see sedges growing with little direct/dappled sun in natural areas, but it's true that very few plants will thrive in heavy, total shade. Even so, they stand a better chance at doing well with shade than turf grasses, though.  Miri

responder: The Question Asker Replied March 31, 2023, 9:38 AM EDT
response: Hi Miri,Thanks so much for all this information! I did some price looking at plugs, and for the square footage I have, it's pretty cost prohibitive. Would seeding grass and maybe planting some hardier shade plants like violas be a better compromise of sorts, ecologically? Thanks so much! AndrewOn Mon, Mar 20, 2023, 3:29 PM Ask Extension <<personal data hidden>> wrote:

responder: Answered by the Home and Garden Information Center (HGIC), University of Maryland Extension. For timely gardening information and tips, subscribe to our Maryland Grows blog and quarterly newsletter. Follow us on Facebook, Instagram, and YouTube. Replied April 03, 2023, 10:31 AM EDT
response: If you wanted to try lawn grasses, fine fescue (or a blend using a significant portion of fescue as fine vs. tall) is the way to go for heavier shade, though it's care regimen is a bit different than for tall fescue. (Mainly minimal mowing and less fertilization, and it's less tolerant of foot traffic overall.) Locally bagged turf seed blends will use fine fescue in their shady mixes. If you opt to go with tall fescue instead, keep in mind that annual overseeding will probably be needed to keep it somewhat dense, though any turf in tree shade will struggle over the long term.  Using wild violets (Viola sororia is one of the most commonly grown or which might appear on its own) would be fine, though they lose leaves in the winter. Their roots should still minimize erosion as they hold the soil, but if seasonal leaflessness is an aesthetic concern, it's something to be aware of. Wild violets do support some native bees and a few local butterfly caterpillars. The aforementioned Mondo Grass, while not native, is another option that would be more sustainable than trying to maintain a healthy portion of lawn in this area. (Native species may be ideal, but anything non-invasive well-suited to the site can still be a responsible choice.) There are a number of native groundcovers tolerant of mature tree shade, but comparatively few that will also tolerate much in the way of foot traffic. As we mentioned before, if the areas that would be walked-on fall along a specific pathway, maybe mulching or using flagstone or stepping stones in that portion while planting traffic-intolerant species in the rest of the space would be the best approach to keep your options broad. (Or, use fine fescue or tall fescue lawn over the walking path and other groundcovers where they won't be stepped on regularly.)  Miri