Osmocote Advertisement

Houseplants

I have houseplants outside that I will need to bring indoors. What is the lowest temperature at which I can leave them outside?

The rule of thumb is when night temperatures are in the 50s, it is time to bring your houseplants indoors, according to horticulturists at Pesche’s garden center, Des Plaines.

To avoid the shock of suddenly bringing plants into a hot dry environment, place them in a shaded area before the heat comes on in the house. Bring in sensitive tropicals such as hibiscus and anthuriums as soon as summer cools down.

Christmas cactus and cymbidium orchids can tolerate chillier temperatures and stay outdoors longer, but move them indoors before the thermometer drops to freezing, says Greg Stack, University of Illinois Extension Educator, Horticulture. Indoors, a cool 50-degree area such as an unheated sun porch will give them the short day situation they need to set flower buds. Stack keeps his Christmas cactus in a cool unused room where the lights aren’t turned on. His plant sets buds and blooms reliably every year, he reports. Christmas cactus buds will dry up in an overheated, dry room.


Peonies

Do the ants on my peony flowers help buds to open, or is this an old wives’ tale? What are the extremely tiny, microscopic yellow wormy looking bugs crawling on my pink peony flowers? My peonies are beautiful, but I don’t want all these bugs.

Peony buds exude a sweet viscous sap that attracts ants. The ants do not generally affect the opening of peony buds. The old tale could have arisen because ants are occasionally seen eating large transparent drops of sap on the buds.

The tiny worms you describe are common yellow thrips, which are attracted to light-colored flowers. Thrips suck juice from buds, petals and leaves. Their triangular bodies are too small and move too fast to be hosed off the plant. A systemic insecticide should be used to prevent plant injuries.

“Peonies are such old time nostalgic favorites that people excuse their shortcomings,” says Mary Ellen Murphy, perennial plant specialist, Pesche’s Garden Center, Des Plaines. “To use the flowers indoors in cut arrangements, pick them when the buds are soft and show color, and then rinse the stems outside with a hose to remove insects.”


Good Annuals for Shade

Now that bedding impatiens (I. walleriana) are not recommended because of impatiens downy mildew, what are three good annuals for shade?

Chris Williams, production manager, K&W Greenery, Janesville, Wisc.

I like New Guinea Impatiens. They make nice bushy plants that are full of large colorful flowers and are easy to grow. You also get a large color selection with New Guineas. The SunPatiens and Bounce impatiens are fairly new plants, and they are recommended for sun as well as shade. Then there’s coleus. Who doesn’t like its colorful foliage? Many varieties grow upright, but others also spread. Torenia, also known as wishbone flower, has trumpet-like flowers of white, yellow, rose and purple that cover nicely mounded, low-growing plants.


Karen Wedel, manager of the outdoor floral department, Wedel’s Nursery, Garden Center, Kalamazoo, Mich.

One of my favorites is begonia. Tuberous varieties have large colorful blooms; wax begonias are good for mass planting. I’m also a fan of the big leaf, 16-20 inch tall Whopper series with large waxy leaves and summer-long flowers.
Another idea is coleus and caladiums. They come in different foliage colors, work great in gardens and containers. They are both also easy-care.
Finally, torenia or wishbone flower, named for the small “wishbone” inside the mouth of the pink, yellow or blue-purple flowers. Blooms all summer. Some varieties will trail.

Kevin DeBoer, manager, Big John’s Farm Market and Greenhouse, Chicago Heights

My favorite is Dragon Wing begonias. They’re usually sold in 4½ inch pots or hanging baskets. At my house I removed them from the baskets, then planted them in the ground in full shade. They turned out awesome! Plain wax leaf begonias are also good.
In addition, I like coleus. They don’t produce flowers, but they have many different vibrant leaf colors. In full shade New Guinea Impatiens will flower sparingly, but if you put them in some sun, they will flower more.


Cabbage Worms

We are first-time gardeners and have planted Brussels sprouts and green and red cabbage that we are trying to grow organically. There are black egg sacs and small green worms eating the leaves. Is there an organic product we can use on the cabbage?

Egg sacs can be washed off with a hose.

There are several organic methods you can use to deter cabbage worms. Lightweight polypropylene row covers, placed over a row of plants and supported by hoops, will block wind and insects while permitting light, air and rain to reach the plants. Hold down the row covers with soil, stones or bricks.

Another organic method uses pots of mint growing between cabbage plants. The mint odor is said to deter cabbage moths. Don’t let the mint take root, however; it will take over your garden. Rotenone dust is considered organic, as it leaves no poisonous residue on plants. The use of hot pepper spray is an irritant to insects and worms, but also to your skin and eyes. Bacillus thuringiensis (Bt) is a specific biological control that is fatal to cabbage worms if ingested. Note that it can be harmful to certain butterfly larvae.


What are some good plant/tree choices to hide unattractive views?

I’d like to block an unattractive view of my neighbor’s house/yard. What are some good plant/tree choices to hide unattractive views?

John Eskandari, owner, The Urban Plantsman, Chicago

Two evergreens for sun are Thuja occientalis ‘Wintergreen’ and Picea pungens ‘Fastigiata’. Both are moderate to fast growers. For shadier locations, Picea abies ‘Cuppressina’ does remarkably well.

A deciduous tree that would work nicely is Fagus sylvatica ‘Dawyck’. It comes in green, gold, red and purple leaved varieties. They work well in shadier spots but the red and purple leaves are less intense in shade.

In smaller areas, I like Amelanchier laevis ‘Cumulus’. It’s a more upright form of serviceberry providing nice spring blooms, edible berries, and golden fall color. It is adaptable to both sun and shade.

Chrissie Sieff, nursery manager, Platt Hill Nursery, Bloomingdale

Whenever I am asked this question, my customers usually have something in mind such as ‘Emerald Green’ arborvitae (Thuja occidentalis ’Emerald Green’, sometimes labeled ‘Smaragd’). They want a green wall, and they want it instantly! Our dead plant return rate is high on this item, so I try to steer them to hardier choices, such as Viburnum nudum ‘Winterthur’ or Syringa pubescens subsp. patula ‘Miss Kim’.

A strategically placed tree can also do the trick. I love katsura tree (Cercidiphyllum japonicum), river birch (Betula nigra), serviceberry (Amelanchier), and ‘Ivory Silk’ tree lilacs. As you can tell, I’m not a big fan of evergreens.

Andy Wedel, part owner, Wedel’s Nursery, Florist & Garden Center, Kalamazoo, MI

Arborvitae (Thuja spp.) is the first plant we think of, but there are others. It’s hard to pick just one. Fine Line buckthorn (Rhamnus frangula ‘Ron Williams’) is a columnar-shaped deciduous shrub with yellow fall color. Evergreen, drought-tolerant upright junipers such as Juniperus chinensis ‘Blue Point’ are great in sunny spots. Some other columnar trees include ‘Crimson Sentry’ maple (Acer platanoides ‘Crimson Sentry’), Red Fox katsura (Cercidiphyllum japonicum ‘Rotfuchs’), and columnar hornbeam (Carpinus spp., cvs.).


Pines in Winter

This past spring I planted a lacebark pine (Pinus bungeana) in full sun. As winter began, the angle of the sun’s rays has caused the tree to receive, at most, 4 hours of sun. What are sun requirements of evergreens in winter?

In general, pines adapt to the winter weather by becoming dormant, says Susan Eyre, Rich’s Foxwillow Pines Nursery, Woodstock. It is the freeze and thaw cycle that is hard on a plant, not the loss of sun hours. In a January thaw, sap rises and then freezes, which can cause the bark to crack, but plants usually recover.


Compost Bin

I’d like to start composting. Do you have any advice on what kind of bin to purchase/build so that it is successful in the Chicago climate?

Compost, decayed organic matter, improves soil structure, porosity and density and creates a better root system. It increases moisture retention and nutrients while adding significant quantities of organic matter to the soil. It is such a valuable addition to garden soil that it is worth the effort to collect and store waste vegetative material until it decomposes.

Compost bins range from low to high tech. A compost heap can be as simple as a pile of leaves stored at the rear of your garden. The most costly composter is a revolving two-tumbler device with a rotator drum that separates new material from finished material and discharges the final product.

Ideally, if you are saving a mix of unshredded plant material that includes flower stems, large leaves and small branches, a three-bin system works best. Stake out three 36-inch square cages using fence rails, lattice or steel wire. Raw material goes into the first bin. When it is partially decomposed, aerate it and shift it to the second bin, and put the most highly decomposed matter into the final bin. With that method, you can keep adding fresh material as the season progresses.

Do not put any diseased plants in the pile. Keep it in a concave shape to hold rainwater, and aerate it occasionally. As the pile “cooks,” it will heat up during the summer. An interior temperature of 180 degrees will kill bacteria but is not often attainable; 120 degrees is more likely for a mix of green and dried leaves.


Rose of Sharon - Botrytis Blight

I have two 3-year-old rose of Sharon plants, about 20 feet apart. One blooms every year. The other plant forms about 100 buds and looks healthy, but it has not bloomed in the last two years. The buds are solidly closed and look as if they are rotting from the inside out. There does not seem to be any sign of insects on the plant. What is this problem?

From the description it sounds like your plant is infected with botrytis blight, a fungus disease that attacks buds before they open, according to Jim Schuster, extension educator, horticulture, University of Illinois. Your plant needs to be treated with a fungicide early in the season. Remove all diseased portions of the plant and any residue on the ground, as the fungus lives over winter in discarded material.


Fruit Trees

I am interested in growing fruit trees in my suburban DuPage County yard. Can sweet cherries be grown here? Can you suggest varieties of apples, pears, peaches, apricots and plums that are hardy and disease resistant?

Sweet cherries are not hardy in this area. Some fruit trees are sensitive to winter cold and spring frost damage to the buds. Early flowering apricots are the most sensitive, followed by peaches. Pears and sour cherries bloom later and are less sensitive to late frosts.

Apples are the least sensitive to frost damage. Apple scab and apple maggot are common pests. Fruit trees require a regular schedule of spraying for pest control.

For a backyard fruit tree grower, tree size is important. Dwarf fruit trees bear full-sized fruit earlier than standard sized trees. Most fruit cultivars need two different varieties to cross- pollinate and produce fruit.

Midwest Fruit Explorers is a non-profit amateur backyard fruit-growing group. For more information about fruit growing, see www.midfex.org.


Slugs

I am sick of slugs. Perhaps if I knew their life cycle I could get rid of them. Where do they go over winter? Where do they come from? What is the best way to get rid of them?

Slugs are gastropods belonging to the mollusk class. They have lungs and can breathe air and live one year. At nightime, to conserve moisture, they feed by biting tissue with a rasping mouth underneath their body. They move by sliding over slime secreted by a large muscular foot and constantly lose water from this slime production and evaporation.

To make matters worse, they are hermaphrodites having both male and female organs and can deposit egg-like clusters of 1/8 inch pearls in soil where they overwinter. Their growth is activated by rising soil humidity and temperature in the spring, according to Ed Valauskas, Manager of Library and Plant Information Services at the Chicago Botanic Garden.

Even if your soil is relatively slug free, they can come in from a neighbor’s yard or live in the soil of container-grown plants. If you garden in very sandy, fast draining soil, you will probably not have many of these pests, but in heavy clay soil, slugs find constant moisture that suits their life style.

Slugs feed on plants with moisture in them, especially hosta, ligularia, dahlia and begonia leaves, lettuce, strawberries and tomatoes. They hide by day and feed at night or on gray, damp days. Go outside with a flashlight after 10 p.m. and look for them under boards, rocks or pots and destroy them.

Laurie Skrzenta of Laurie’s Landscape, a Downers Grove hosta grower, keeps the hosta area dry and doesn’t water them because slugs do not live in dry locations. She depends on rainfall and maintains that hostas can exist without supplemental water. Laurie also suggested using coarse sand as a mulch. Another possibility is to sprinkle sand in the center of your dormant hostas since this is where the slugs lay their eggs.

There are many home remedies to get rid of slugs including beer, ammonia water, ice water, and yeast water. Gardener Anna Hevrdejs, Woodridge, suggests sprinkling corn meal around slug areas. Slugs like to eat it, then die. Replace it after a rain. She also claims that sweet woodruff planted around hostas restrains the slug population.

Chemical metaldehyde or methiocarb pellets are useful but they can be attractive to dogs and children. They are very toxic. Much safer is a copper strip laid around the areas to be protected, although this is not practical in an ornamental garden.


Page 1 of 9 pages  1 2 3 >  Last ›

categories

popular

Article Thumbnail
Columns
Plant Identification Flow Chart
A comical plant identification flow chart from our columnist, Mike Nowak.

Article Thumbnail
Columns
Friends Don’t Let Friends Plant Mint
If “ignorance of the law” is no excuse, does that apply also to the laws of nature? Of physiology? Of reproduction?

Article Thumbnail
Columns
The Dirt on … Oh Never Mind
By the time you get to this page (that is to say, if you’ve read all or most of this magazine), your brain is so crammed with …

Article Thumbnail
Departments
From the Editor
For me, one moment above all others elicits that life-is-good feeling: the germination of the first tomato seed on my radiator.

Article Thumbnail
Columns
Basement Bounty
Decisions, decisions. What’s a devoted gardener to do with brugmansia as winter approaches?

questions

How do I contact customer service?

I have two 3-year-old rose of Sharon plants, about 20 feet apart. One blooms every year. The other plant forms about 100 buds and looks healthy, but it has not bloomed in the last two years. The buds are solidly closed and look as if they are rotting from the inside out. There does not seem to be any sign of insects on the plant. What is this problem?

I start ‘Dragon Wing’ begonia from seed under grow lights. What other begonias can I use to cross-pollinate with the ‘Dragon Wing’ so I can collect my own seeds?

ChicagolandGardening Advertisement