Green Scene

Autumn Gardening Quandaries: Falling Leaves and Edible Dogwood Fruit

By Joel M. Lerner
Saturday, October 17, 2009

The leaves are changing colors, and the weather's turning crisp. That means it's time to answer some of your fall gardening questions.

Q: Do I have a fig tree? I have a plant whose leaves have a fig appearance, but its fruit looks like burrs. -- Marion Snyder

A: Even though the leaves of your plant look like a young fig, don't be deceived by what you see. The fruiting sharp burrs are the telling part. This is typical of a cocklebur (Xanthium strumarium), a toxic plant.

Q: I want to plant a red maple seedling that I dug and potted last spring, but if deer don't eat our plants, they trample them. What's the best method of protection for this seedling? -- Joyce Rizzolo

A: Try protecting the seedling in two ways. Surround it with a flexible wire, mesh or plastic fence that has one-inch openings and is firmly attached to wooden or metal stakes. Fashion the wire fence as tall as possible -- four to six feet high -- even if the seedling is only six inches high. Tree tubes are another way to shield your tree. These can also protect trees from rabbits and rodents, as well as from birds pecking on the bark.

Q: I am using copper sulfate to attack the black rot on my Concord grapes. The company that makes it assures that it is a fully natural product that can be used up to a day before harvesting, as long as users rinse the grapes before eating them. Can you give me a second opinion about using copper sulfate? -- Mrs. Peterson

A: Common copper sulfate is one of the weapons recommended for control of black rot on grapes, one of their most common diseases. Copper sulfate is a natural product, which means it occurs naturally in our environment. This mixture lasts for only a short time on plants and washes off relatively easily. However, it is not safe to breathe, eat or get on your skin for an extended period, so protective measures are a good idea. The most important ingredient in the product for fighting the fungus is copper, and the worst place to absorb copper is in your eyes, so wear goggles. Follow all the instructions on the product's container.

Accompany your spraying program with thorough cleanup of all signs of fungus as soon as you see it. That includes pale spots on grapes and any dry brown grapes. Your fall cleanup should be meticulous. Don't leave a diseased leaf, branch or grape anywhere on site. Keep the area pristine through winter, and preen it regularly through the growing season. Pruning tools should be treated with bleach after cutting away diseased parts of vines. Spray a little light oil onto the pruner after cleaning to keep it from corroding.

Q: Will falling leaves smother grass seed or newly growing grass? How can I remove leaves without disturbing the new grass growing underneath? The leaves fall well into November. Is it possible to put off my lawn program until all the leaves have fallen and are removed? -- Aldo Pileggi

A: Mow the leaves on your lawn into tiny particles that help fertilize the soil. If the leaves become thick, grind them with the mower or take them to the compost pile. If the leaves mat on the lawn, they can weaken and kill the grass. Keep heavy leaf accumulations off the lawn and continue mowing until grass growth ceases in November or December. Do not put off lawn treatment. A valuable part of fall aeration is that small leaf particles fall into aeration holes, mix with the seed and fertilizer and hold moisture. As you rake or mow leaves, the materials you spread will remain and mix together. Keeping the lawn mowed and clean going into winter also reduces the chance of having snow mold or other winter-fungus-related lawn diseases. Once grass germinates, walk on it only for maintenance, until tender young seedlings mature.

Q: My friend has a zoysia lawn and I have fescue. I mow almost every week, fertilize spring and fall, use weed control, and do the other tasks you recommended in your recent column. He mowed twice this summer and does nothing else to his lawn. Is zoysia the best way to minimize carbon emissions from noisy lawn mowers and reduce fertilizer, pesticide and herbicide runoff? -- Bob Forbes

A: We are on the northern cusp of hardiness for zoysia. That means it should do well here only when we have mild winters. It will die with deep freezes for long periods. My only bias against zoysia is its spreading nature. For example, if your friend is your neighbor, his zoysia could grow into your lush green lawn in fall, creating brown areas, ruining the aesthetic value of your deep green, cool-season turf during the spring and fall. If you have a lawn because you want a green, manicured appearance, zoysia will provide about six months of green. A cool-season grass offers about eight to nine months.

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