Cover the ground, not the daffodils

QUESTION: What groundcovers can be used that will allow daffodils to come up in the spring?

Spring bulbs will grow through English ivy, but there are better groundcover choices to use.

Several plants used as groundcover permit spring-flower bulbs to grow through. Nashville-area garden specialists offer a few recommendations:

Ajuga, or bugleweed (Ajuga reptans). To some people this is a nice groundcover, to others it’s a weedy nuisance. It can be aggressive, but in the right spot it might be just what you need.

Periwinkle (Vinca minor), grows in shade, is green all year, and has pretty blue or white flowers in spring. Please note: Vinca minor is listed among the invasive exotic plants in Tennessee. Please use responsibly.

Daffodils will also push up through English ivy (Hedera helix), but because it, too, is an invasive exotic that can climb trees and displace more desired species, I would never suggest planting it in the landscape.

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March: In like a lion

I’m writing this shortly after coming up out of the basement, where we hunkered down for a few minutes Friday afternoon while a possible tornado loomed. The sound of the hail pounding down was tremendous.

I tell you this to let you know that the March Landscape & Garden Calendar, which runs the first Saturday of each month in The Tennessean, starts up again March 3. I say there that meteorologist Bobby Boyd has told us to expect a turbulent spring. Nevertheless, it’s time to get out into the garden again. Look here for the story; go here for a .pdf version of the calendar.

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The Nashville Lawn & Garden Show is this weekend, 10 a.m. – 8 p.m. today (March 3); 10 a.m. – 5 p.m. tomorrow.

Good luck with ‘bamboo’

QUESTION: I have a “lucky bamboo” plant in a pot of water with pebbles that looked great for awhile, but now it has grown big shoots out of each of the stalks. Can I cut off these shoots and re-pot them?

The first thing you need to know about lucky bamboo that it’s not bamboo at all, but a plant in the genus Dracaena (specifically, D. Sanderiana). Its close kin includes two other popular houseplants: corn plant andMadagascar dragon tree.

Growers of this easy-care plant suggest not cutting it from the top, but you can remove the extra shoots from the stalk with a sharp knife. Cut it flush with the stalk if you don’t want another shoot to grow in the same place. If you do want a shoot to re-emerge, cut it about 1/8-inch out from the stalk. You can try to root the cut-off shoots in water: Dip the ends in rooting hormone powder and let them dry overnight, then place the shoots in water. Eventually, new roots may grow. You can grow lucky bamboo in water or in soil.

These are relatively low-maintenance plants, but you do need to pay attention to the water they’re in, and add water as it evaporates so the roots don’t dry out. Every week or so, pour out the old water and add fresh, preferably filtered water, or tap water that you have allowed to sit out overnight.

Keep lucky bamboo out of direct light and away from extreme heat or cold, and feed it every couple of months with a very dilute solution of plant food (about 1/10 the recommended strength, plant care specialists suggest).

Upcoming events

-Nashville’s native plant expert Margie Hunter is the guest at the February 21 meeting of the Perennial Plant Society. Her topic is “Going Natural in the Garden: Let Nature Be Your Guide.” The meeting is in Cheekwood’s Botanic Hall. Refreshments at6:30, meeting begins at 7, and is open to the public.

-Spring is on its way! The Nashville Lawn & Garden Show is March 1 – 4  the Tennessee State Fairgrounds. Gardens, exhibit booths, lectures and more. Details here.

-In Putnam County, the Upper Cumberland Home & Garden Show is March 2 – 4 at Hyder Burks Agricultural Pavilion at Tennessee Tech inCookeville. Vendors, speakers and more, 4 – 8 p.m. March 2; 9 a.m. – 8 p.m. March 3; noon–4 p.m. March 4.

-The Nashville Rose Society is holding its annual Vendor Night at the March 6 meeting. This is the chance for rose growers – and all gardeners — to shop for supplies from mid-state vendors. 7 p.m.in Cheekwood’s Botanic Hall. The event is open to the public, More on the Nashville Rose Society here.

-The Middle Tennessee Daffodil Society Spring Show is March 31 and April 1 in the Potter Room, Cheekwood’s Botanic Hall. More about MTDS here.

-And it’s not too early to get these on your calendar, because these are events you won’t want to miss:

The Perennial Plant Society’s annual sale is coming back to the Tennessee State Fairgrounds April 14,9 a.m. – 2 p.m. There will be thousands of perennials for sale for sun and shade, all fromTennessee growers, so they’re adapted to our growing conditions. Admission is free, but PPSMT notes that the Fairgrounds has a $5 parking fee. To learn more, visit the PPSMT’s website here.

The Herb Society of Nashville’s annual plant sale is April 21 at the Tennessee State Fairgrounds. It’s 9 a.m. – 2 p.m., but get there early to browse through 15,000 herbs (including some of those hard-to-find varieties) and talk to the Answer Ladies and all the other herb fanciers who turn out for this annual event. Look for more info at the Society’s website here,  and on Facebook here.

Sweet surprise: sweet potato vines

QUESTION: The ornamental sweet potato vines I grew in large pots last summer produced potatoes – to my surprise! Can they be replanted to produce vines next year?

Sweet potato vine (Ipomoea batatas) ‘Blackie’

Yes! The sweet potatoes that are grown for their ornamental vines don’t have much taste, but U.T. Extension agent David Cook says you can save the tubers to produce the same foliage next year. Here’s how to do it:

If the potatoes haven’t already frozen (and by now, you may find that they have, unfortunately), dig them up and store them packed in straw in a dry, cool place. When the weather begins to get warm again, the tubers may begin to sprout. Cut them into sections just as you would cut a seed potato, with at last one “eye” per section. Allow them to dry for a few days, and plant them in the ground after the frost date has passed (mid-April here in Middle Tennessee).

Ornamental sweet potato vines come in a variety of fancy-leafed “flavors.” ‘Blackie’ is an easy-to-find favorite, with purplish-black, deeply lobed leaves. ‘Ace of spades’ has heart-shaped leaves. ‘Tri-color’ is variegated with green, white and pink foliage, and the variety called ‘Marguerite’ has golden-green leaves.

The vines grow fast, and are a striking addition as a “spiller” in a container, draping elegantly over the sides. I learned last summer that rabbits find the leaves tasty. If your garden has a resident rabbit (as mine does), you’ll find the vines will start to disappear, so be warned.

Don’t worry about the daffodils

It’s only January, and the daffodils in my yard are already coming up! How do I keep them from freezing?

Early risers: daffodils can survive winter.

It may seem too early for this unmistakable sign of spring, but it’s not unusual for the shoots of early daffodils to begin pushing up through the ground. In some places, they started coming up before Christmas. The best thing to do is: Nothing. In fact, there is nothing you can do. Spread some pine straw over the daffodil bed if it makes you feel better, but really, even that is an unnecessary step, says Anne Owen of the Middle Tennessee Daffodil Society.

We’re at the mercy of the weather fluctuations, but generally, a blast of cold weather won’t hurt the daffodils, Owen says. The worst that could happen is that the weather turns warm and stays warm enough for long enough that the daffodils bloom; then the flowers might succumb to a snap of extreme cold. If we get a freeze while only the leaves are up, they should survive without a problem.

Good reading

It’s a good time to sit down with a stack of seed catalogs (or a list of seed company URLs) and plan this year’s kitchen garden. Here are some of my favorites (where I indulge in a little wishful thinking):

Seed Savers’ Exchange (Unusual varieties not found at the big box store seed kiosks)

Seeds of Change (Seeds, supplies, and live plants, too)

Territorial Seed Company (Try out the online garden planner)

Southern Exposure Seed Exchange (“Particularly suited to the Mid-Atlantic and similar regions”)

Renee’s Garden (Pretty as a cottage garden)

Baker Creek Heirloom Seeds (Recipes included!)

John Scheepers Kitchen Garden Seeds (Straightforward, with tidy line drawings; more tips and entertaining reading at the website)

Brent & Becky’s Bulbs (One of the best sources for bulbs, say those in the know)

Burpee (for sheer volume, and all those luscious pictures!)

Keep African violets blooming

QUESTION: My African violets were blooming beautifully when I got them a few months ago, but no longer. How can I get them to bloom again?

It’s easy to love those dainty clusters of blossoms rising from rosettes of downy leaves. African violets look like they’d be fussy plants, but quite the opposite: “They’re easy to grow if you know a few secrets,” says Julie Mavity-Hudson of the Nashville African Violet Club.

One of those secrets may surprise you: African violets tend to bloom better when they’re slightly root-bound, so don’t rush to move them to larger pots. They thrive in bright, indirect light and average room temperatures, in soil that is kept slightly moist. “The thing that kills more African violets than anything is overwatering,” Mavity-Hudson says.

Failure to bloom might be because the plant is not getting enough light. In winter, when the light is low, try moving it to a south or west window where the light is brighter, but move it away from the window when the light is more intense. Direct sun will burn the leaves of African violets.

A light feeding of high-phosphorous plant food every few weeks may also help. Houseplant expert Barbara Pleasant (The Complete Houseplant Survival Manual) suggests adding a light pinch of Epsom salts to water to push balky plants into bloom.

To get together with other African violet aficionados, check out the Nashville African Violet Club, which meets the first Sunday of most months,1:45, at the Green Hill Women’s Center,10905 Lebanon RoadinMt.Juliet. The meetings are open to the public.

Events coming up

– Professional Landscape Association of Nashville, Tennessee – P.L.A.N.T. – will hold its winter seminar Thursday (Jan. 12),8 a.m. – 4 p.m., in Massey Hall atCheekwoodBotanical   Garden. The day’s topics include “Right Plant Right Spot,” by Kerry Mendez; “Pruning Techniques & Best Management Practices” by Karla Kean; Perennial Plant Collector’s Corner by Kerry Mendez; and “Longwood Gardens’ Vision for Horticultural Excellence and Beauty,” by Rodney Eason. Registration at the door is $100 for P.L.A.N.T. members, $125 for non-members (includes lunch). To learn more, visit P.L.A.N.T.’s Web site here.

–Another reminder that the Nashville Lawn & Garden Show is March 1 – 4 at the Tennessee State Fairgrounds. This year’s theme is Gardens Past, Present & Future, and as always the show features beautiful live gardens, 250 exhibit booths, a floral design gallery and a roster of free lectures.

Peter J. Hatch. The Thomas Jefferson Foundation Inc. at Monticello, photo by Robert Llewellyn.

Peter J. Hatch, Director of Gardens and Grounds at Monticello, the home of Thomas Jefferson, is one of this year’s speakers. Hatch is scheduled to speak on Friday, March 2 about “Thomas Jefferson’s Revolutionary Garden,” which featured more than 330 varieties of vegetables. On Saturday, March 3, Hatch will discuss Jefferson’s use of native plants, the union of gardening and sociability, and his experimentation with useful plants as a means of social change in his talk, “Thomas Jefferson, Gardener.” Other popular speakers are returning: Jeff Poppen, The Barefoot Farmer from Long Hungry Creek Farm in Red   Boiling Springs,Tenn.; Rita Randolph of Randolph’s Greenhouses from Jackson, Tenn.; and Justin Stelter, historic gardener for Carnton Plantation in Franklin and The Hermitage, Home of Andrew Jackson. Information about these free lectures is at the Nashville Lawn & Garden Show Web site.

Admission will be $10 for adults ($9 if you’re 65 or older), and this year the Tennessee State Fairgrounds will charge $5 per vehicle to park during the show. The Web site promises group discount and coupon offers coming soon.

Making plans for a great year in the garden

QUESTION: What are YOUR garden goals for 2012? Here are mine:

-Grow more flowers. In my yard, that means finding more flowers that thrive in the semi-shade that’s provided by the graceful maples and the giant, beautiful elm tree in our back yard.

-Keep trying for better success with tomatoes. That means figuring out how to outsmart squirrels. (Maybe I should give up on tomatoes in the kitchen garden out back and move tomato production to my garden plot at Farm in the City, the community garden I belong to downtown.)

-Double the produce by doubling the space for growing. I’d like to take on another raised bed at Farm in the City if there’s one available.

-Grow better peppers. I know that the secret is lots of sun and consistent water. There’s a lot of sun at Farm in the City; I need to work on the water part.

-Okra: plant less, pick more often.

-Grow more pole beans. Grow more cucumbers. Try squash again.

-Plant more shade-tolerant herbs. This is a project I started last spring – finding herbs that can grow happily in the shadiest of the eight raised beds in the kitchen garden out back. Success so far with curly parsley and red-veined sorrel. Hope to plant sweet woodruff and more borage, maybe nasturtium. Still trying to find lovage.

-Make peace with the wildlife in the backyard, while at the same time finding a way to keep the rabbits from eating the hostas.

-Plant more big, blooming perennials and annuals in the three little garden beds at Mom’s house.

-Visit as many public gardens as I can manage (especially interested in visiting Eudora Welty’s home and garden in Jackson, Miss. this spring).

-Enjoy every minute I can spend gardening, and writing, talking and teaching about gardening.

What plans do you have for your garden this year?

Rubber tree can bounce back

QUESTION: I have a huge rubber plant that is very old. I’ve had to tie it to stakes in the pot to keep it from growing in all directions and out of control. Can I prune it?

A rubber plant, or rubber tree (Ficus elastica) can be transformed from an unmanageable mess into a more dignified plant. It takes a little planning and observation, but the results can be worthwhile, and can provide more plants in the process.

Before you make the first cut, look at the plant to determine how it might look after it’s pruned. New leaves will grow where you cut it, so keep that in mind as you remove the branches. The cuttings you remove can be placed in water, where they will often form new roots. After they grow a good system of roots, they can be potted in soil.

Houseplant experts also suggest a process called air-layering to prune old plants and grow new ones. This is accomplished by cutting into the plant’s stem where you want to prune it. The cut is then wrapped in moss and plastic wrap, and new roots grow from the cut area. After new roots form, cut off the new plant and pot it separately. Early spring, when the plant is entering a period of active growth, is a good time to try to trim it into shape.

Here are general guidelines for keeping a rubber plant alive and well: bright to moderate light (no direct sun) and average room temperature. Keep the soil evenly moist. A rubber plant probably does not need as much water during the winter. It can spend summer outdoors in a protected location, but be sure to bring it in before temperatures begin to drop in the fall.

O, Christmas pine

QUESTION: I’m using a Norfolk Island pine as a small Christmas tree. What do I need to do to keep it looking nice, and how do I care for it when the holidays are over?

Norfolk Island pine provides a nice alternative to the big tree at Christmas, especially if your space is small or your decorating is simple. It’s best not to load it down with large, heavy ornaments that could break the feathery limbs. Use lights sparingly, if at all, and remove them as soon as you can after Christmas is over.

When it’s time to change it from a Christmas tree to a houseplant, place it in a spot (preferably in a cool room) that gets bright, indirect light – a south- or west-facing window is good – and give it a quarter-turn once a week to encourage it to grow straight up.

The biggest threats to Araucaria heterophylla (that’s the tree’s botanical name) are dry soil and dry air. Keep the soil consistently moist, but don’t let the pot sit in water. Increase humidity in its environment as much as possible. A daily misting could go a long way toward keeping the plant healthy. If the air remains too dry, the Norfolk Island pine responds by dropping its needles, and once they’re gone, they don’t grow back.

Houseplant specialists suggest using a balanced fertilizer once a month in summer, and be on the lookout for pests. Spider mites and mealybugs are drawn to this plant. A cautionary note about placing it outdoors: it’s a very tender plant, and will be damaged if the temperature falls below 40 degrees.

With care, a Norfolk Island pine can last for many years. They grow very large in their native South Pacific environment, but in a home, the tree usually grows, over time, to about 6 feet.

 

Water in winter

Landscapers know this, but we casual gardeners may not remember that even though it’s winter, the garden still needs water. Pay special attention to newly planted trees and shrubs, broadleaf evergreens (which continue to “breathe” even during winter), pansy beds and perennials that you planted in the fall.

Mulch keeps soil from drying out too quickly, but if the weather is cold but very dry, the soil will eventually dry out.

 

Events

A couple of garden-related events coming up:

- The Tennessee Gesneriad Society will meet Jan. 8 at 2 p.m.at Cheekwood in Botanic Hall. The program will be a slide show on Gesneriads. For more info contact Julie at Julie.mavity@gmail.com or 615-364-8459.

- The Perennial Plant Society is planning its January meeting and welcomes visitors. The guest on Jan. 17 will be Alan S. Windham, Ph.D, Professor of Plant Pathology with UT Extension in the UT Institute of Agriculture at Ellington Agriculture inNashville. He’ll speak on “Hot Topics On Diseases of Perennials.” Refreshments served at6:30 p.m., and the meeting begins at7 p.m.

No-fly zone

QUESTION: Some of the plants I brought in from outdoors seem to have tiny white flying bugs all around them, and are a nuisance. What are they? And what can I do about them?

 

Schefflera can play host to whiteflies.

These are likely whiteflies, and they often ride in on plants that spent summer outdoors. They’re more than a nuisance; they feed on the plant’s juices and can cause the leaves to turn yellow and die. The insects that are flying are the adults, and if you look at the undersides of the leaves you may be able to see the tiny yellow eggs and larvae.

Whiteflies feed on dozens of plant species and they reproduce quickly, so the problem could get out of hand quickly. To get rid of them, remove the badly infested leaves, then rinse the plant thoroughly and spray with an insecticidal soap. Be sure to treat the undersides of the leaves. Repeat the spraying every week or so.

Next fall, examine them closely to be sure there are no pests hitching a ride. Wash the leaves and treat the plants before you move them indoors. There are several other insect pests that you should watch for:

Aphids: they usually gather in clusters on tender young leaves. They also feed on a plant’s juices. Insecticidal soap, or washing with water or rubbing alcohol, is usually effective.

Mealybugs: You may see white, cottony clusters on stems or leaves, or where the leaf joins the stem. They also feed on the plants, so get rid of them by rubbing them off with water or alcohol.

Spider mites: They are barely visible, but you’ll certainly notice the damage – light-colored, speckled areas on top surfaces of leaves. You may see webbing stretching between leaves if there is a heavy infestation. Wash the plant with soapy water, and treat with insecticidal soap a day or two later. It may require diligence and several applications to control these insects.

UT Extension provides a booklet at its Web site that addresses these problems and more: Insects and Related Pests of House Plants (PB1157).

Poinsettias in the spotlight

QUESTION: I like to decorate with poinsettias for Christmas. What’s the best way to keep them looking good from now until New Year’s?

Poinsettias are a tropical plant, native to Mexico, so the first thing to remember is to keep them out of the extreme weather. If it’s a cold day when you bring them home (less than 50 degrees), don’t leave them in the car too long, and make sure they are protected on the trip from the car to the house.

Once inside, place them in a spot that gets indirect light. They’ll do well and last longer in a room that is not overly warm – 68 to 70 degrees is just about right. Keep the soil moist, but not soggy. Most likely the plastic pot will be wrapped in foil; it’s best to take the foil off when you water, to avoid trapping water that will cause the roots to rot. If the leaves become dry and curled, that’s a sign that it needs water. If a poinsettia wilts, that’s an indication that it may be getting too much.

Those are the basics for keeping a poinsettia looking cheerful through the holidays. If it starts to look a little sorry after that, don’t feel bad about tossing it into the compost. However, as often happens, a poinsettia can surprise you by pushing on healthy and strong into the New Year, and it’s a shame to discard something that’s growing so vigorously.

So, let it grow. Keep the soil moist and it should continue to thrive. As spring approaches, cut it back to about 8 inches tall and fertilize with an all-purpose plant food, and after there is no longer any danger of frost, re-pot it and set it outdoors, or plant it in the ground where it can survive as a nice, interesting green plant all summer (and succumb to its inevitable fate at the first sign of frost).

Here’s an interesting tidbit that comes from California poinsettia grower Paul Ecke Ranch: National Poinsettia Day is coming up! Dec. 12 marks the death of Joel Roberts Poinsett, the first United States ambassador to Mexico, who gets credit for introducing the plant to the U.S.