Q: A neighbor and I were discussing the question of cutting back perennials in the late fall. Are there general rules? The tags that come with new plants give great directions for watering and fertilizing, but say nothing about preparing the plant for winter.
This conversation started because I have some new Montauk daisies this year that are still in beautiful bloom right now. One neighbor said they should be cut back to a third; another neighbor has already cut his down to the ground. That's one species, but there are many others to wonder about.
A: In general, perennials are cut down when the frost has killed the foliage. But for the majority of plants, this is more for the sake of the gardener and to tidy up the garden for the winter. Many perennials can be pruned in the late winter or early spring as the garden is springing back to life. I'd have to have the names of specific plants in order to be more accurate with advice. I'm puzzled — why would your neighbors want to cut his Montauk daisies down before they've finished blooming?
Montauk daisies grow best when changes are made while the plant is dormant. Cut them back or transplant in early winter, after several hard frosts. They will retain some leaves through the winter if cutting is left until spring.
Next year, to increase blooms, pinch them like mums until mid-July, then let them grow! This will give you more flowers with less "flopping."
Let me know about the specific other perennials so I can give you better information.
Q: I miss my garden already! If I wanted to dry a few flowers instead of buy them this winter, can I still do it? Is there anything worth drying so late in the season?
A: You should have begun earlier! But there are still some materials that you can dry. They aren't the colorful flowers you could have picked and dried in mid-summer but there are still some grasses and weed and seed pods on the roadside that are fun, useful and attractive. And dried flowers are free!
Cut plant materials responsibly (cut, don't pull). Stay away from beach grasses, which are protected by law as they are needed to control erosion. And always check with the owner of the property before you cut anything.
Next year, begin to dry plant materials earlier in the summer. They will keep you company through the long winter ahead.
Q: I brought in a lovely magenta and lime green coleus well over a month ago. While outside it flourished and was quite beautiful. However, since bringing it in, despite being in a sunny window, the leaves are no longer flat and full. They are still colorful, but lean downward and even curl under a bit in places. I can't give it more sun than it has now as it has sun a good part of the day and I'm certain that it has enough water. Can you give me any suggestions?
A: There have been some mighty cold nights in the last month. Did the plant get nipped by cold weather (under 45 degrees) before you brought it in?
You may be giving the coleus too much sun. Bright, filtered sun is enough, or just some morning sun. They should grow well in normal illumination.
Are you fertilizing? Fertilize with an all-purpose houseplant food at half strength every few weeks.
The curled leaves make it sound like there might be some sort of a bug. Watch for bugs! They will tend to congregate on the underside of the leaf. Even if the plant was perfectly healthy this summer, bugs could have "hitched a ride" on the plant as you brought it into the warm house — and thrived. Wash the underside of the leaves with cool water — and use a soap spray. Re-spray at one-week intervals so you get every bug — and every egg they lay. Two of the most common bugs are spider mites, and mealy bugs.
Water coleuses well, but don't let the plant stand in water in the saucer for more than a few minutes!
Do consider taking cuttings from this plant as we go through the late winter. Coleuses that you grow from cuttings will be ready by the time we've had the last frost in May, and fill up the windowsill with glorious color in the meantime.
Q: Hello, enjoy your column. It mentioned the overuse of coffee grounds in the garden, but did not have the information I need. Would appreciate your advice. I was told to put coffee grounds on some plants, mainly hydrangeas. I have been putting them on other plants too. Is this too much?
A: Coffee grounds are used on acid-loving plants like blue hydrangeas, azaleas, rhodys, evergreens, roses and woodland plants. Overuse occurs mostly because gardeners throw heaps of them around their plants — more is not better!! And we have to remember that we live in New England, where the soil tends to be acidic anyway — so test soil periodically to avoid overuse. When coffee grounds are applied and not spread or mixed into the soil, they cause the same problems as wet leaves: the ground starts to mold! They are great mixed into the compost pile, and increase acidity and boost nitrogen and add texture, particularly to clay soil.
Did you know that coffee grounds also seem to repel slugs and ants? And mixed with orange peels, they will repel cats from the garden.
Q: Is it too early to begin cleaning up perennials such as cone flower that have gone by, but still have green foliage? Also, I planted a butterfly bush in August and it has done well. Should I treat it a as a perennial and cut it down to the ground before winter, or as a shrub to be pruned in the spring?
A: Cut coneflower down after foliage dies — or leave it, as you wish.
The seed-filled pods are winter interest in the garden — and provide food, particularly for finches and other songbirds until you do your spring clean-up.
Butterfly bushes can be pruned anytime — and benefit from pruning, since they bloom on new wood. But in this climate, you're better off pruning in the late spring after the last frost. Remember that these bushes can be very late to show growth each spring.
A real plus in leaving the pruning until spring is that the dead branches will mark the spot where the bush is growing, which you might miss since the plant is very late in showing new growth every spring.
This fall, you might mulch gently around the base of this new planting, although this shouldn't be necessary, unless we have an unusually cold winter. You really can't kill a butterfly bush! (In the Northwest, they are considered invasive.)
End of season dirt
It's Thanksgiving weekend — but you have some things to do before you head into dinner:
Drain outdoor water pipes and hoses. Self-drain faucets don't stay ice free if a hose is still attached — detach hose and put aside if you wish to continue to use the faucet into freezing weather to clean gutters and tools. Otherwise, drain hoses and put them away in a frost-free storage place.
Clean tools — wash off mud and grit now! It's much easier to clean tools in the fall and have them ready to go in the spring.
Brass faucets, Siamese connections etc., which are badly corroded, can sometimes be cleaned by soaking in vinegar to clean corrosion. Use a glass jar or a plastic container and soak in vinegar. Sometimes it takes a week or more of soaking, but it usually works! Dry and lubricate moving parts and put them away for the winter.
In-ground irrigation stems need to have water blown out to prevent freezing and bursting of pipes. Rent a compressor and share the cost with another neighbor needing to do the same job.
And of course, gutters must be cleaned as soon as the leaves are completely down but before they can freeze in the gutters, which will make clearing them almost impossible. Be sure to do the downspouts — flood them with water to be sure they're clean.
THEN you can finally drain and put away the hoses until spring ... and enjoy the turkey!
Happy Thanksgiving!
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North Shore Gardener by Barbara Barger of Beverly is a regular feature of the Home North section. Reach Barbara by e-mail at nsgardener@comcast.net or write to her c/o Salem News, 32 Dunham Road, Beverly, MA 01915. Past North Shore Gardener columns are available at www.nsgardener.com.
