Pruning now could make roses vulnerable to damage

By Audrey Post
MS. GROW-IT-ALL

Q: My Knockout roses really need to be pruned, and I know you said the best time to prune roses is in February but they really look shaggy now. Will I kill my Knockouts if I prune them now?

A: Maybe not, but you’ll certainly upset their normal growth rhythms and you could be putting them in jeopardy. If you prune them now, you’ll signal to them to get ready to start growing. That won’t be a problem if we have a mild fall and winter. But if your rose bushes are in full-fledged growth when a hard freeze hits, it will likely damage them and, depending on the severity of the freeze, could possibly kill them. That’s why we prune roses in February, so they can get a jump-start on growing after the freezing season.

They might look a little ragged now, but you’ll really be better off if you wait until February to do any hard pruning. This isn’t like pruning azaleas, which are evergreen. A late season pruning likely will remove any buds for next year’s azalea flowers but it won’t jeopardize the plant itself. It’s designed to live through frosts and freezes in our area. Pruning a rose too late in the season could do nothing or it could kill it. It all depends on the weather.

Q: I planted a small wildflower meadow but it didn’t produce many flowers. Should I reseed it for next year?

A: Yes, I would sow a few more seeds in your meadow this fall. So many things affect the germination rate of wildflower seed – the availability of water, heat, the age of the seeds – and it takes several years to establish a wildflower meadow. Scatter a few more seeds to increase the odds of germination and flower production. Once established, the flowers will re-seed each year.

Make sure you’re using a mix of wildflower seeds blended specifically for the Southeast for the greatest chance of success.

Internet Radio Show: Ms. Grow-It-All’s Internet radio show now broadcasts live at 6 p.m. Wednesdays at http://www.blogtalkradio.com/Ms_Grow-It-All. Just cut and paste the link into your browser window. If you can’t join us live, you can download a podcast from my Web site. This week’s topic was preparing your lawn for winter. Next Wednesday, our topic will be planting a garden for wildlife.

Homemade remedies treat black spot on roses

By Audrey Post
MS. GROW-IT-ALL

Q: What can I do about black spot on my roses? I would prefer to avoid chemicals and go with something more organic, even if it means I have to treat the rose bushes more often?

A: Black spot is a fungus, Marssonina rosae, that causes dark-colored spots to appear on the leaves, hence its name, and then the leaves turn yellow and die. It’s a common problem in areas of high humidity and frequent summer rainfall.

Some cultivars are more resistant to black spot than others, and you can keep the fungus in check by removing fallen leaves and pruning the canes in late winter (mid-February in North Florida). Avoid overhead irrigation, if possible, and water early in the day.

There are a number of fungicide products on the market, but since you want to avoid using chemicals, here are two potions that friends recommend: Mix fat-free milk and water in equal parts and spray it on the foliage; or dissolve a tablespoon of baking soda in a quart of water, add a squirt of dish soap and spray the mixture on the leaves. The soap makes it a little sticky so it adheres to the leaves. Whichever one you choose, you’ll have to apply it regularly, at least once a week, if not more often.

If readers have other suggestions, send them to the e-mail address at the bottom of the column and I’ll share them.

Plant giveaway: Jerry Patton, the Tallahassee gardener who gave away numerous plants last year, including daylilies, crape myrtles, hollies and night-blooming cereus, has another “crop” ready to share.

“I just can’t throw any plant away,” he said. “I trim them and plant the cuttings.”

This year, he has lots of night-blooming cereus, which he ran out of last year, as well as century plants (Agave), passion vine (Passiflora) and butterfly milkweed (Asclepias). He also has what he calls a “mystery plant” or two, nice potted plants but he doesn’t know their names.

Call him at 850-878-1321 for directions to his home.

Internet Radio Show: Ms. Grow-It-All’s Internet radio show on the Free World Radio Network will broadcast live at 6:30 tonight. Leon County Forester Stan Rosenthal and I will discuss lightning and gardening. Go to http://www.blogtalkradio.com/Ms_Grow-It-All and click on the link to listen live; you can call the number on the site to join the conversation. If you can’t join us, all shows are archived and available for download from my Web site.

Prune roses in February

By Audrey Post
MS. GROW-IT-ALL®

It’s February, and that means it’s time to prune roses here in our corner of the gardening world (USDA Zone 8b). The general rule is to prune around Valentine’s Day, which was last Saturday, but we still have a few weeks to get the job done before the big flush of spring growth begins.

As with any task, gathering the right tools make the job much easier. You’ll need sharp hand-pruners and loppers. You’ll need to wear gloves, too. I suggest getting long gloves that cover your forearms as well as your hands, because rose thorns hurt. If you can’t find long gardening gloves, use long fireplace gloves.

Make sure your cutting tools are sharp and clean. If you don’t want to sharpen your tools yourself, local garden centers can either sharpen them for you for a fee or direct you to a business that offers tool-sharpening. Once your tools are sharp and you’re ready to begin, clean and disinfect them with a bleach solution (1 cup of bleach to a gallon of water) and keep a bucket of fresh bleach solution handy, in case you encounter diseased canes on your roses.

First, identify any dead or diseased canes and remove them back to the ground, dipping your cutting tool in the bleach solution between cuts. Then, from the remaining canes, identify which ones are younger and which ones of the older ones can be removed.

As you’re deciding which canes to remove, be mindful of the overall shape of the bush and the direction you want each cane to grow. For younger, healthy canes on bushes that have been pruned annually, remove oldest canes, usually two or three, and cut back the younger canes by about half.

For bushes that haven’t been pruned annually, remove the really old canes – they’re tough and gnarly; you’ll recognize them. Cut back the remaining canes back to half their length. Then cut a third of those back farther, to about a third of the length they were before you began. Make cuts at a 45-degree angle just above a bud or “eye,” making sure the bud is pointing outward from the plant. Next year, identify the canes that didn’t get the most severe cut this year, and cut half of those back to one-third. The following year, do the rest. That’s the “rule of thirds” for rejuvenating roses and many other shrubs.

Remember that keeping the plant to a reasonable size is only part of the reason for pruning. You also want to open up the inside of the bush to light and air circulation. Remove any canes that cross back into the bush, as well as any of the twiggy branches that are smaller than a pencil in diameter. Remove any foliage that remains on the plant.

If any suckers have sprouted below the graft, break them off flush instead of cutting them. That way, you’ll get the basal bud, too.

Radio Show: Care and pruning of roses

This week's show was all about care and pruning of roses, an appropriate topic for this Valentine's Day. Click on the link to Blog Talk Radio in the right rail to listen to the show for seven days after its initial broadcast. If you missed that one-week window, an archive of all our shows can be found at http://www.freeworldradionetwork.net/.

Prune fall bloomer in early spring and mid-summer

By Audrey Post
MS. GROW-IT-ALL

Q: I have a very healthy cassia (Senna bicapsularis) that gets extremely overgrown and "leggy" during the summertime. Because this is a fall-blooming plant, I am afraid to prune it back during this time. Can you please tell me what time of the year is the very latest that this plant can handle pruning?

A: Most plants should be pruned shortly after their bloom-period is over, and cassia is no exception. It blooms in fall and in mild climates will continue to bloom throughout winter. You can prune it now through March to get it ready for the next season's growth, but that shouldn't be the only time you prune it.

Fall bloomers such as cassia need pruning in early spring to get them ready for their growth cycle, and again in mid-summer to shape them for bloom season. So trim back your cassia again in mid-summer to keep it from getting leggy. July is best, but you can prune through mid-August and still ensure fall flowers on your cassia. Pruning any time after that means you risk having an early frost interrupt your bloom cycle.

Q: I have a rose bush that needs to be moved. A tree has grown to shade the location where it was planted over seven years ago. I know the rose is still healthy as it manages some blooms after the tree sheds its leaves in the fall. When should I move it to a sunnier location? The bush has some wicked thorns and would be next to impossible to move without pruning.

A: February is the time to prune roses, and it makes sense to move them at the same time. Don't try to fight the thorns. Cut your rose bush back to about 24 inches, then dig it out and move it to a sunnier spot.

Tool time: Larry Hale e-mailed to remind everyone that now is the time to make sure our tools are in proper shape to help us garden over the next year.

"This is the time of year gardeners should take a file and sharpen all their tools. Sharpen shovels and hoes to make spring soil prep easy. In old Tallahassee, we could always depend on a gentleman coming by once a year to sharpen all our tools. He was always seen traveling with his mule and wagon.

"I'm amazed at people who try to dig with blunt shovels."

Larry's right. It's much easier with sharp tools. If you don't have a file or don't want to do the work, most local garden centers either offer the service or can recommend someone to do it.

Don't fertilize Knock Out® roses until spring

By Audrey Post MS. GROW-IT-ALL®

Q: We have 11 Knock Out® rose bushes, which my husband feeds two-thirds of a cup of 6-6-6 Blooming Rose Fertilizer monthly. They have grown to about 4 feet high and bloomed beautifully over the spring and summer. Should we keep applying rose food throughout the fall and winter months? Also, should Knock Out® roses be pruned? If so, when should we prune them and how much?

A: Knock Out® roses have become among the most popular shrubs in the home landscape, thanks to their ease of care and prolific flowering. They’re disease-resistant, drought-tolerant and self-cleaning – meaning no dead-heading of spent blooms. They’ll bloom from spring until the first hard-freeze.

I would lay off the fertilizer through the fall and winter months. You might get a few blossoms here and there as our temperatures do their normal fluctuations, but you don’t want to keep the plants in high gear for growing and blooming over the winter. New growth is more susceptible to freeze damage, and consequent damage to the entire plant might result.

If you have room to let them continue to grow larger and they’re holding a good shape, leave the pruning shears alone. If you want to keep them to a smaller size and shape, prune them in early spring – which for North Florida is February. It’s a matter of personal choice and space. One friend said hers grew to a 6-foot tangled mess the year she didn’t prune them; another never prunes hers and they stay about 4 feet tall and wide. Soil and climate differences can play a big role.

If you choose to prune your Knock Out® roses, cut the shrub back to about 12 inches. As it grows throughout the season, use hand-held pruners to snip off wayward branches that are outpacing the others to maintain the shape.

Q: When Tropical Storm Fay blew through in late August, most of my sloped back yard was under water for a few days. The St. Augustine grass at the top of the slope, closest to the house, seems to have recovered but the grass farther down where it is shadier is still looking sad. What should I do?

A: From your description, it sounds as though the grass at the bottom of the slope was under water longer, so it makes sense it would take longer to recover. Lack of oxygen can drown plants as well as people.

The fact the area is shady is probably slowing down the drying-out process. Make sure there’s no mulch helping to hold in moisture right now – you want to give the water a chance to evaporate – and wait and see. Anything else you do right now would probably interfere with your grass’ ability to recover on its own. Grass slows its growth this time of year, so not seeing new growth doesn’t mean it’s dead.

If the barren appearance bothers you, spread some ryegrass seed over the area once it’s no longer soggy. If it sprouts, you’ll know the area is drying out and your St. Augustine likely will reappear next spring. If not, you’ll have to decide whether to re-sod, plant something else or create a mulched area.