There is a problem growing roses to close to veggies. They get diseases & don't think natural stuff works all the time. I've moved my strawberries & onions away from the rose garden. Mildew, black spot, scale etc all require something to get rid of them, rust, leaves orange stuff I sure don't want on my strawberries. Years ago it was not so humid, now that climate has changed some they don't work close together. Don't know about the lattice, didn't know any of it was PT mine isn't. I do have cedar 12 in wide boards, rough on 1 side that is still like new. I saw guy taking it off his house & asked if I could have it. Most was 8 ft long 12 in wide & 1 in. thick. Made a gate from some, made walkway(nailed down) all over in attic & use rest in garden around strawberry bed in winter so helps keep from freezing & by mini rose garden so wind doesn't whip off the leaves & so they are protected some. Looks like when I got it & I've had it at least 5 yrs.Cedar is at least 30 yrs old. My lattice is just about 20-30 yrs old & it did used to be thicker, I have couple of sheets newer & it has had to have repairs & I've added small nails to keep it together. Roses don't do much climbing, you have to wire them on or tie them on with string or twine or they will flop over. I have a 40 yr old yellow peace climber with huge flowers & it stands alone most of time or run wire from top of patio cover to it to hold it up & pink peace in corner of yard has a fan shaped support that I wire it to some. Maybe New Dawn or some like that would go through the lattice as their habit is more delicate(I think) the peace climbers get canes 2 in. thick or more. You need some room in front of roses before the veggies to trim out wild growing canes,or tieing them up so your veggies aren't in shade. Good Luck!