Any way to keep my St Augustine from invading neighbor’s Zoysia?

travelguy73 – posted 06 October 2011 09:15

Sorry for a long first post!

My next door neighbor has an established yard of Zoysia (he doesn’t know what variety). We have an established yard of St Augustine. Both are in mostly sun.

Until now, there has been a property line flower bed that separated them, but we want to get rid of it and give the yards a more open feel (and it has become a pain to maintain since their Zoysia keeps invading it!). Since it is on my property, I want to sod with more St Augustine. My neighbor doesn’t seem to care if the grasses grow together as there is only a couple of feet of the Zoysia before his concrete front walkway (and he knows I will mow it now, LOL), so it can’t invade very far. But I do mind if they grow into a messy mix of grasses, especially if the result is that the Zoysia grows into my St Augustine!

From reading other posts, it appears that the St Augustine is probably more aggressive than the Zoysia, so…

1) would a simple steel edging from one of the big box stores run between the two grasses do any good? (2) If we decide to resod his patch of Zoysia with St Aug (the 2′ that connects to my lawn), will the Zoysia be hard to remove?(3) Any other tips or advice?

tommy – posted 07 October 2011 13:42

Probably go with one type of grass, (remove the zoysia). Spray ‘Round up’, wait a week and then mow short to expose runners. Spray again, wait another week, and then dig up the dead turf and replace with St.Augustine.

RealGreen5 – posted 07 October 2011 18:12

We often experience problems with St Augustine running into either Zoysia or Tif Bermuda. There are some chemical treatments available but they are hard on both grass types. Have seen homeowners cut a small 2-3″ ditch between the two which has been lawns that has to be maintained to allow nothing to cross over. Nurseries sell a metal mechanincal border that is also very effective in keeping the undesirable grass from crossing over into your lawn. Both are successful and have to be maintained but are much less harsh than chemical controls that are limited in how effective they actaully prevent the transfer. With Zoysia be extra cautios with chemicals as all the varieties burn fairly easy with a product strong enough to effectively control the undesirable type. It is certainly worth it as it makes a beautiful lawn when well maintained.

RealGreen5 – posted 07 October 2011 18:17

Mechanical Borders work much better than chemical controls as they do not stress the desirable turf. If you do not wish to have the border in place a small 2-3″ trench between the two lawns has worked very well for many of our customers. Either of these have to be well maintained but are very effective in preventing transfer of undesirable grass into the Zoysia

seed – posted 08 October 2011 15:10

Mechanical borders such as 4×4 landscape timbers, partly set in the soil, can exclude St. Augustinegrass because its only horizontal stems are stolons (above ground) and not rhizomes (below ground). This was also answered for bermudagrass:https://turfgrass.com/ubb/Forum1/HTML/000217.html

This same won’t work in reverse, because zoysiagrass and bermudagrass have rhizomes and can grown underneath the timbers.