Q My lawn, for the most part, is Bermuda except for an area around a tree which is St. Augustine. I have been covering the St. Augustine when it's really cold to prevent winter kill. Can I just cover the St. Augustine with the leaves from the tree during the winter, or would that harm the grass?
A St. Augustine is usually winter hardy in central Arkansas. Severely cold winters can cause some loss, but covering a lawn for winter protection is neither feasible nor advisable. Letting the lawn go dormant naturally is preferable to covering with leaves. A light leaf mulching is fine, but you want to see the lawn through the leaf cover. A heavy layer of leaves left on a lawn all winter can smother out the grass and will cause more harm than help.
Q When is the best time to prune cannas and hydrangeas? Both of my hydrangeas did not bloom this year and did not grow as much as the year before. I may have pruned them at the wrong time last year. Thank you for your help in this. I really missed these plants not blooming this year.
A Cannas have gone dormant for the winter, and now is a great time to cut off the spent foliage. Adding a little fresh mulch around the base can give them some winter protection. We want to take the old foliage off to help prevent leaf rollers from overwintering in the dead leaves. For hydrangeas, you need to know which type you are growing to know when to prune. Most people grow the large flowering Hydrangea macrophylla — the ones that are pink or blue. They bloom on flower buds that they set before they go dormant. So, the dead-looking sticks now contain the flowers for next summer's blooms. If we have a cold winter and they get killed back to the ground or they are pruned, they won't flower the next season. (There are some varieties, like "Endless Summer" and "Blushing Bride," that have been bred to bloom on old or new wood.)
Oakleaf hydrangeas are similar in their pruning requirements. If you are growing the panicle type or the "Annabelle" type (H. paniculata or H. arborescens) they bloom on the new growth and can be cut as severely as you like before growth begins.
Q I have a yard in Little Rock that is half Zoysia and half St. Augustine. I bought a new mower that has a mulch setting. Which is better for my lawn, mulching or bagging? I have a ton of leaves that fall in my lawn. I had always been told that oak leaves take too long to biodegrade for lawn mulch. Is this correct?
A A mulching mower comes in handy when leaves are beginning to fall. A light layer of mulched leaves is a great way to add some organic matter back to the soil. Now that the majority of the leaves are off the trees, I am afraid that you would have too many mulched leaves left behind on your lawn if you used the mulching mower. Shredded leaves break down much faster than large, whole leaves, but too much of anything isn't a good thing. If you have a bag that can be attached, mow the leaves and use the shredded leaves that end up in your bagger for mulch in flower beds, vegetable gardens or pathways. Shredded leaves also are excellent fodder for a compost pile.
Q I read with interest your article on abscission layers. That explains why my large Japanese maple by our front door is loaded with dead leaves. Even with all the wind, we have been having, they seem pretty secure. Not so for all the oak leaves, which I have spent the past two days bagging. We normally put Christmas lights on the tree, and I don't think it is going to be an easy task with so many leaves. Is there something you suggest?
A You aren't alone with your Japanese maple still having leaves, but there isn't much you can do. I would bet some leaves will fall as you decorate, but I am worried that you would damage the tree if you tried to remove the leaves manually. Maybe consider using the net lighting that you can throw over the whole tree. Good luck, and happy holidays.
Retired after 38 years with the University of Arkansas Cooperative Extension Service, Janet Carson ranks among Arkansas' best known horticulture experts. Her blog is at arkansasonline.com/planitjanet. Write to her at P.O. Box 2221, Little Rock, AR 72203 or email
jcarson@arkansasonline.com
HomeStyle on 12/07/2019