I'd suggest using one of the dwarf Carex species such as Carex praegacilis or C. pansa. Dwarf Mondo Grass would probably also work, but would appreciate more periodic watering to get it established. Planting any of these in late October/November would be the preferred time to get them best established using the rainy season to get them off to a good start. I wouldn't suggest trying a true moss as ground cover unless you are willing to water it during the summer, or accept the fact that it will go brown and dormant without any irrigation during the dry months. Dymondia will also take a bit of shade, but isn't at its best unless it gets at least half day sun.

St. Augustine is pretty-much the most shade tolerant of the turf grasses. Growing grass under oak trees can be difficult for several reasons. The heavy/thick canopy of the oaks creates a deep-shade underneath them. You can selectively trim some limbs from the canopy, without destroying the shape and beauty of the tree. This will allow more light through the canopy. My friend grew a beautiful vegetable garden every year, under two very large beautiful Live Oaks. The vegetables got only about 3 hours of direct sunlight a day. The rest of the light was gained by thinning the canopy. Oaks exude "tannins" that cause major problems for some plants. This is what was used for many years to "tan" animal hides with. Plants like Asian Jasmine seem to tolerate tannins just fine. As was mentioned above, large trees of any type will use a lot of the nutrients and water available underneath themselves. You will have to provide extra feeding and watering to keep a nice lawn under oaks or any other trees.

Dear Doucanoe, Thank you very much for your inquiry. Grass in the shade is not easy as you have found out (if it was, it would be in all the domed stadiums around the world, including the Metrodome.) That being said, the keys here are choosing the right grass and then maximizing the sunshine and air circulation. There are only a couple of choices for best shade grass in your area. If you have irrigation, the best choice hands down is supina bluegrass. It even spreads in the shade. However it must have moisture and it is expensive as it is not grown in the US. It can cost up $40/lb, and if the seeding rate is 2.0lbs /1000 ft2, you can get expensive in a hurry. If you go this way, one alternative to cut costs is to buy perennial ryegrass as a companion crop and mix at 90/10 P. ryegrass to Supina. The supina will spread throughout the lawn as the ryegrass dies and you will have a nice lawn soon. If you do not have water, then you need to choose fine fescues for the area. These do quite well in low light and persist in dry soils without much fertility needs. The trick with all shade grasses is establishment. This is where thinking Âmaximizing sunshine time comes into play. Circle mid-September on your calendar as this is the time when we want to establish the grass, just before the tree leaves turn and fall off the trees. We want to use the late fall for growth and then the sun from early spring to get all the growth we can before the tree leaves comes out and rob the sunshine from the grass again. We center our fertilizer schedules on these time periods as well. This way we are not fertilizing a grass in the shade when it needs sunshine with the fertilizer to complete its growth cycle. Finally, if there are areas where you can prune a few branches and improve sunlight, this is a worth effort. Also, all efforts to clear underbrush and allow air circulation will be rewarded by better turf as well. Sunshine and air movement are the keys. Again, thanks for the question and let me know if you have more. Respectfully Trey Rogers The Yard Doctor

According the the ASPCA, vinca minor is TOXIC to dogs. . All systems will be affected- neurological, gastrointestinal, and respiratory .. you may see a loss of coordination, seizures, diarrhea, vomiting and respiratory depression- aka (Stop breathing) Ivy is poisonous as well. Here is the ASPCA collection of toxic plants. Please review for e sake of your fur babies https://www.aspca.org/pet-care/animal-poison-control/toxic-and-non-toxic-plants