Q: How do you get rid of Zoysia grass? I have tried everything and it just keeps coming back. R.B. Kansas

Zoysia is a tough customer- I know, my neighbor has some and every year it keeps creeping further and further into my bluegrass, which drives me nuts. Zoysia is a great grass type for southern states, but for places like Kansas and Ohio in fact anywhere that temperatures drop regularly well below freezing, it is definitely not recommended.

As to getting rid of it, you're not going to like this. It pretty much takes half the growing season to knock it out completely. The problem is that its roots go deep and killing the top foliage only sets it back and then it returns. Not as much as before, but any remaining Zoysia will spread. So, here it is: you have to apply a complete foliage killer such as Roundup. This kills everything, including your bluegrass. Then you have to leave the dead area alone until the Zoysia offshoots begin to sprout. Another treatment is then applied. This process continues and can take several months to completely remove the Zoysia.

Control of spreading grasses is usually attempted with a non-selective systemic herbicide like Roundup. Best results are seen when the weedy plants are young, fully green, actively growing, and not under drought stress. The mother plants are easily killed, but often the plant will re-grow from the stolons, rhizomes or dormant seeds in the soil. To overcome this, more than one application is recommended. Allow the plant to re-grow before the next application. At least two applications are recommended, but more may be needed.

You must realize that the area will be dead and unsightly for a number of weeks or months if optimum control is desired. Once you're satisfied that it's not coming back, then prepare the soil and plant new seed / sod.

OPTION 2: Another method that is a little faster involves removing all of the infected area sod. Include some of the top soil when removing the sod. Once the sod is removed, wait before laying the new sod to see if any additional plants emerge. If so, treat as above. If after 2 weeks of non-growth, go ahead and lay the sod. If you're going to plant seed, you'll need a little additional top soil spread to compensate for that which was removed.

If you're living next door to a neighbor with Zoysia, you should think of putting in a barrier between the two lawns. One method would be to set in some landscape edging meant to go around garden areas to keep the grass from invading your planting beds and mulch from sliding into the grassy areas. This is available at most nursery or home improvement stores. It's typically black with some ridging along the side and comes in 25' or 50' rolls. Dig a narrow trench along your property line, bury the edging so that the top of it is just about 1/4" —1/2" above your neighbor's soil line. Back fill with dirt, then plant your seed or lay the sod.