As far as the chemicals go, I figure anything that’s going to kill plants chemically seems like it’s got to be bad for something.
I generally try to avoid using them. I do use poisons and baits for rodents and ants.
ANTS. Those are another patio problem, not so much at the main house in question, but at my current home that has tightly fitted bricks on top of a sand base. The ants carry out sand making those little sand dunes. Clearly brick patios (or any flat stone in the middle of a yard) make a nice protective cover for an ant colony.
A patio is really nice in winter, and really anywhere you’re going to commonly walk. Also, to compare to furniture left in a grass lawn, it’s easier to pick weeds a few times a year than it is to move furniture every time you want to mow the lawn. Plus it feels cleaner to sit on it without concern for bugs jumping all over you. Solid top tables and umbrellas will end up killing grass anyway too.
I’m trying to figure out what to do with this back yard. I will probably work on the drainage with the adjacent neighbor to see if we can agree on a solution that’s mutually beneficial. I’m thinking of rearranging the brick patio so the low areas are soil, not brick. I figure the rainwater is going to always bring debris to the low areas. So I will constantly be cleaning off bricks if I leave it this way. Also, the roots from the tree are so large that leveling the patio with soil might not be practical. Furthermore, having grass so close to the swimming pool that gets cut or weedwacked will always result in more debris in the pool to be cleaned out. So I’m thinking that making the patio more focal on the pool might be beneficial. Perhaps chairs outside the pool fence might seem like they are arranged around the pool.
In the picture below, the area in blue floods. To the left of it is a raised bed that captures the water on my property until the water level gets over the raised bed, at which point it floods my neighbor’s yard. So the more permeable I make the ground, with plants that will absorb the water the better. There is a dry well in this location that has pipes that I believe just distribute the water to different locations in the yard, like under the raised flower beds. I am thinking that it might make sense to remove bricks from this area as the patio is already so bumpy here, and move them to the right side of the yard around the pool fence.
I also believe there were two additional trees near this low point in the yard. Perhaps it will make sense for me to plant another shade tree. I don’t know. I am not in a rush to get this done, but was certainly overwhelmed with the amount of weeds growing out of the patio this week. It’s not yet at the point where the brick patio seems like a lawn that needs mowing, but I’ve had a property where that was the case. We just started mowing the patio as if it was a lawn. I ultimately removed the bricks and was pleased with the sodded lawn solution I replaced it with.
Using the information people have shared in this thread, I will figure it out, and as I re-lay the bricks, I will be sure to use media that will be less likely to invite weeds. THANK YOU!!