My kikyua grass is patchy and ugly. Do I need to sow some seeds onto it?
This type of grass needs full sun; perhaps surrounding plants have grown up and are shading certain areas. Here's an article that may be helpful:
https://www.gardeningknowhow.com/lawn-care/lgen/what-to-do-for-a-receding-lawn.htm
Do I need to take a soil sample and send it for sampling? The buffalo is native and in the front area of the yard very difficult to get a good stand
Overwatering or fertilization are possible problems, but it may be worth getting the soil sampled, as you suggested.
Here's an article with some watering and fertilization info:
https://www.gardeningknowhow.com/lawn-care/specific/buffalo-grass/care-of-buffalo-grass.htm
My grasses have gotten big around and I want to reduce their size. I tried cutting a section out but roots seem impossible to cut. How can I reduce their area?
Here are tips to cut ornamental grasses. You must dig them up, then cut with a root saw or chainsaw if they are large.
https://www.gardeningknowhow.com/ornamental/foliage/maiden-grass/dividing-maidenhair-grass.htm
Please recommend solution to kill off weeds as the photo attached
I can't see what the weed is from that photo, but you will want to get a selective herbicide for that particular weed.
Here is an article that will help:
https://www.gardeningknowhow.com/plant-problems/weeds/using-herbicide-in-gardens.htm
Big problem with couch grass invading lawn. I thought if I painted a few leaves with glyphosate it will kill it - but will it transfer through the roots to other grass that it is displacing ?
Whatever does make it to the soil will be such a small amount that it won't really harm anything. Now, if you are spraying, then the stuff won't be selective. It will kill almost anything in its path.
Most people have a larger area to kill couch grass and must spray good grass and couch grass. Once the couch grass is eradicated, they must reestablish good grass.
I need to move my firecracker grass as it has gotten too big for the area I have it in. Should I cut it back when I move it or stake it up for a few days in the new location?
It's best not to move anything in bloom. This article tells more about how to prune them. If you wait till spring, or when it is not actively growing, you can cut it almost to the ground, then divide and move it.
Here is more:
https://www.gardeningknowhow.com/ornamental/foliage/fountain-grass/fountain-grass-pruning.htm
Live in central Virginia. Want to plant grass seed now in October but I have three Bradford pear trees in my back yard. Here, they do not stop dropping their leaves until late November. Do I just let the leaves lay on top of my grass seed or do I wait until late November to plant when I have the leaves cleaned up ?
The seed should be able to work its way down into the soil. Mulching over with leaves after seeding is a good idea.
https://www.gardeningknowhow.com/garden-how-to/mulch/mulching-with-leaves.htm