Turfgrass for Shade in Brooklyn

This is the Moss Garden at Ryoanji (Peaceful Dragon Temple) in Kyoto, Japan. Moss gardens require years of growth, great care, devotion, and plenty of irrigation, but they are doable. I have been working on one out in East Hampton for a number of years now and patching are beginning to merge.

Question:
I have a house in Brooklyn with quite a lot of trees that shade the property. I would like to grow grass on the property. Can you recommend a grass that would thrive in the New York City climate in the shade? Also, I am very intrigued by the Grasspave2 product at invisiblestructures.com -- are you familiar with this product and would you recommend it? It seekms to make for a very hard-wearing but attractive grass surface.

Answer:
Thanks for writing. This is certainly a question I could go on and on about but I will try and keep my reply brief.

The reason I could go on and on is because at heart I’m really more of an arborist, and my personal love is trees. Trees thrive in a fungal-dominated soil where turf, because grass is a herbaceous plant and not a woody plant, tends to prefer a more bacterial-dominated soil. Mixing the two can be tricky because it’s not as natural a combination as most people like to think. Again, to revert to my arboreal nature, when you take a walk in the woods under established trees you simply do not find turf grasses. So, right off the bat I can say that this might not be the easiest task, but as we have seen here and there people have made it possible to incorporate both trees and turf in a small area.

Before I get to grass options, let’s talk amount of shade. Depending on how large and established the trees are, you want to first think about how much shade you are really dealing with. And without seeing the site this becomes more difficult for me to speak to, so you’ll have to make a few judgment calls. If the area underneath is so shady that right now nothing is growing, except maybe a few weeds, then grass might not be the best option. Proper horticulture is all about the right plant in the right place, and trying to force grass in too shady a location it simply won’t take and you’ll just get frustrated. If some light gets through, what we’d call dappled shade, then that can still be tricky for growing turf grasses. Many ferns as well as shade-tolerant plants like hostas and astilbe, those kinds of plants will do fine in dappled shade and can fill in a space pretty successfully in the course of a couple years. If there are large shadows cast by the trees but otherwise some direct sun hits the ground then turf grasses are perfectly viable.

Scott’s and other large scale gardening companies have made great strides in terms of the products they offer. Scott’s has shade tolerant grass seed mixes that, if the light is dappled shade or better, should take just fine. (I just checked and unfortunately their website is down, but you will see there products in any major retailer or garden center). Not always, but most of the time shade mixes have a combination of ryegrass, fescue, and bluegrass. Ryegrass is incorporated because it germinates quickly and gives you some instant gratification, but ryegrass doesn’t last forever. As it fades, the fescues and the bluegrasses take over. Fescues are great for both their shade and drought tolerance, but take a long time to germinate and get established. Bluegrass used to be more of a sun loving turf grass, but as growers have grown and cultivated new varieties there are more and more shade tolerant bluegrass species on the market every year.

I once wrote an article on alternatives to traditional turf grass species and here is a little excerpt from that as well:
“For turf style grasses in a shady environment turn to the sedges. Catlin sedge, Carex texensis, is a fine, short sedge well suited for partial to full shade. Even though considered to be tolerant of sun, you might find that too much sun will lead to faded foliage and the need for more water. Hardy from zone 6 down to zone 10, this is an excellent choice for hot climates of the south. For the same success in cooler locations, turn to Pennsylvania sedge, Carex pensylvanica. Also a short, fine sedge for shady applications, Pennsylvania sedge is a strong alternative due to its tolerance for a wide range of soils. An amazing characteristic of both these sedges, as passed on by a colleague of mine, is that they only need to be mowed two or three times a year. The third recommendation for this category is the finest textured of the three, Carex senta, or Baltimore sedge. Very similar to Carex texensis, Baltimore sedge performs excellently in shade. For this sedge, however, you may find that it requires more regular mowing than others.”
Sedges you will not find in seed form, but more sold as established plants. I would hope that some local nurseries in Brooklyn sell sedges along with their grasses.

As for that Grasspave product, I am not familiar with it, but based on the reading I have done, I do not think I would recommend it for a situation such as yours. For a larger area where vehicles are being driven often (playing fields, car dealerships, driveways) maybe that system is of benefit, but for a property in Brooklyn I would again focus more on planting the right plant for the right place. Different grasses have different wear tolerance as well as recuperative potential, two phrases you will want to familiarize yourself with more, and if you can find shade tolerant mixes with those additional characteristics you should be fine. Since you are probably going to be dealing most with basic foot traffic I would fear that investing in a product like GrassPave might be a waste of money. Once we figure out the best grass for your property then we can talk about how to best care for it. People can gravitate towards strong chemicals and extremes when simply cutting your grass at the optimal height along with proper fertilizing will help minimize basic wear and tear and allow you to maintain an attractive property.

Evergreen issues in San Francisco, California

Question:
I have a garden with a large american elm, which faces two different evergreens, one a spruce and one a fir. On the branches that face the elm I have experienced lots of dropped needles. is there something about the roots or other element of the tree, like pheromones or some sense of closeness to other trees, which may be playing a role? this has been happening gradually over the last few years, and the evergreens in question are about 25 years old, with the very nearby elm pre-existent by at least as many years. but the pattern is striking, and would
suggest that to me. any advice would be appreciated.

Answer:

Well, sure enough, a picture is worth a 1000 words, but I hope my advice doesn't go on quite that long! First, I want to clarify the two evergreens. The tall, more cylindrical tree (images 2385 and 2387) is neither a spruce nor a fir. It clearly is a scale-leaf evergreen which means it is most likely an Arbovitae or possibly a kind of Chamaecyparis. Arbovitae are a popular screening tree for that kind of narrow location where everyone is trying to achieve more privacy and screening. The catch is that Arbovitae need full sun to be their happiest. Therefore the holes/patches of defoliated branches are clearly signs to me of too much shade. The other tree (2386 and 2392) you are right, is either a kind of spruce (Picea) or fir(Abies). Here is a quick way of figuring out which one it is. Grab a piece of branch that has both needles and bare stem, meaning a piece closer to the center of the tree. Next, pull off a few needles one at a time. Spruce, when you pull a needle, leaves a little bump, or "peg" where the needle emerged. Hence the catchy phrase, "Picea have pegs". If you pull the needles and they take a tiny piece of the bark with them, leaving a clearly "circular leaf scar" where the needle emerged, then that is a fir tree. Generally people say that spruces are more hard and prickly and firs are softer and more fragrant, but typically that is not enough for a concrete plant ID. However, either way, both spruces and firs, yup, like sun also. Sounds to me, Aaron, like it's not an issue of a disease at all. And yes the space is limited, and for the roots as well, but honestly I think the problem is much simpler. The elm is slowly shading out the other two trees. It grows as fast as the other two, especially if the other two don't get enough sun, its canopy casts more shade, and it makes sense that you have been watching this gradually happen over the last five years. The Arbovitae is going to continue to lose needles on the side facing the elm because that's the shadiest. The fir/spruce/? will also continue to drop needles from the base upwards. You have new growth on the tips of both evergreens so they are still alive, but just getting out competed for the necessary sunlight. At a cost arborists may be able to come in and thin out the canopy of the elm to allow a little more light through, but it might be worth thinking about what you want to do in the long run. Certainly you can cut the dead branches off the evergreens because they will not leaf out again from those spots.