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White Pine Burn

I have two 20-year-old pine trees whose needles are turning brown on the west side of the plants. On the east side I have a compost pile.

I live in the St. Charles region and my soil is mostly clay. What is causing the browning? Should I get rid of the compost? How do I correct the damage?

Climate conditions could be the cause of the brown needles. There was strong west wind this past winter season, which caused winter burn. With last fall’s rain and winter snow cover, the soil never dried out. According to Todd Mohr, sales associate, Rich’s Foxwillow Pines Nursery, Woodstock, pines normally begin

to go dormant in late August. “We had a lot of burn on our evergreens which showed up over summer,” says Mohr.

Cut a sample of the branch and make sure the plant is alive. You can photograph your tree or take the sample to an arboretum or garden center for evaluation. The compost should not affect the trees unless you have a large pile that is prohibiting air circulation. Spread the compost loosely over the area.

White pine is a native Illinois tree. It may come back on its own. If not, have a tree professional diagnose it.


Staking Plants

I dislike staking perennials. Is there anything I can do to avoid it?

There are several techniques you can use to limit time spent on this chore, but it is difficult to totally

avoid staking some plants.

First and foremost, the old adage “right plant, right place” means full sun perennials need to be grown in full sun for tight upright growth. If they are too shaded, the plant will stretch or bend toward the sun and grow in a loose habit. Growing plants a little closer together also helps because it enables plants to support each other.

The best remedy to avoid staking is to cut some tall plants down by one-half in June. That will delay flowering in helenium, monarda, platycodon, chrysanthemum and aster, but the plants will remain upright. If you really want to eliminate cutting back, grow dwarf versions of these plants.”
Short, thin branches from forsythia or dogwood (known as “pea staking” in England) can be placed around the perimeter of newly emerging plants to help keep the stems upright. Some garden centers have begun selling bundles of branches for this purpose. In a short time, the shrub cuttings are covered by emerging shoots. This technique works well with fine foliage such as baby’s breath or flax.

There are numerous staking supports from bamboo to iron rebar rods. Wire staking supports are available in full, half and even quarter circles to support single stems. Peony hoops can be left in place over winter and will support not only peonies but boltonia, baptisia, and even errant tomatoes.

Some plants always need to be staked. Giant dahlia tubers need a heavy stake dug into the hole at planting time. That prized, single-stemmed iris, lily, or delphinium can get blasted in a storm, and then it’s too late to save it.

Remember: the time to stake plants is during the cooler days of spring when plants are growing rapidly and not on humid July days. Staking should be done unobtrusively and subtly for plants to retain their natural grace.


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.


Strawberries

I have two strawberry plants in a hanging basket in my yard. I have not had any fruit from them although the vines hang down. I give them plant food once a month and water daily. What am I doing wrong?

Fertilizing your plant with a high nitrogen fertilizer causes excessive leaf growth. Clip the runners so the strength goes into flower and fruit production. In winter, make sure the plant roots do not freeze in the hanging basket, according to Joni Cotton, Hawthorn Gardens, Hawthorn Woods.


Begonias

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?

‘Dragon Wing’ is a unique hybrid type of begonia named to reflect the shape of its leaves. It is created by interspecific crosses of two different begonia species and can lead to interesting new plants, but they are sterile.

It is impossible to say exactly which species will cross and which will not cross. You can try crossing angel wing begonia, a common houseplant, with another species. There is a good chance viable seed will be produced, according to Brian E. Corr, new crops development manager at Ball Horticultural Company, West Chicago.

The American Begonia Society (begonias.org) is a resource for information on hybridizing. The archives of the bi-monthly journal The Begonian would also be helpful.


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.).


Tree Position

What is the correct distance from my house to plant a tree? What is the correct distance from the lot line to plant a tree?

It depends on the size of the tree you are planting. A small tree such as a serviceberry (Amelanchier) or a dwarf flowering crab could be planted as close as four to five feet from the house. For a birch tree, a distance of six to eight feet would be the minimum.

Distance from the lot line does not matter as long as it doesn’t interfere with power or sewer lines. You should check with your village before planting. Closeness to the neighbor’s lot line is not an issue, because neighbors have the right to trim back any overhanging branches, according to Matt Zerby, partner in Wasco Nursery, St. Charles.


Fertilizer

What ratio and amounts of fertilizer would you use for a perennial bed and a vegetable garden? For growing annuals in a greenhouse, should the fertilizer be fast or slow-release, organic or inorganic?

Use 3 to 5 pounds of a 10-5-10 or 10-10-10 fertilizer per 1000 square feet in the perennial bed. Add leaves as mulch. In your vegetable bed, nutrients are important. Fertilize more heavily using a 10-10-10 fertilizer at the rate of 5 to 10 pounds per 1000 square feet.

For hanging baskets of annuals in a greenhouse, a slow-release fertilizer is best. Use a 20-10-20 liquid fertilizer following label directions. In general, organic fertilizers have a lower chemical analysis than inorganic ones, so you have to use more, according to David Tyznik, owner of Planter’s Palette, Winfield.

A healthy plant is dependent on its soil. A balanced soil is rich in beneficial microorganisms that improve the soil structure and supply necessary nutrients. Soilless potting mixes have no microorganisms. “Both organic and inorganic fertilizers work well, but those in soilless mixes need more fertilizer,” says Tyznik.


Hibiscus

I am growing my potted tropical hibiscus indoors for the winter. The leaves are starting to yellow and fall off. Should I give the plant iron and should I fertilize it? Do I cut it back, and if so, when?

Hibiscus leaves turn yellow in response to the change in environment. The older leaves fall off first. If the leaves are chronically pale yellow with green veins, the plant could be lacking iron, but in your case, it is probably the change in growing conditions that is affecting the plant. When the days get longer in February or March, prune it to shape it, or cut it down to force good bottom growth.”

“Don’t panic; the plant expresses itself dramatically,” reassures Mike Geimer, owner of Geimer Greenhouses, Long Grove. “Don’t be timid pruning it.”


Peony Blight

Last summer my neighbor told me the black spots on my peony were a blight, although my peonies bloomed nicely. What can I do about this?

Your peonies probably have a fungal disease, a common problem. The causes are wet summers with cool damp nights, too much shade, poorly drained soil, or a lack of air circulation. While your neighbor diagnosed your problem as peony blight, which is caused by an air-borne botrytis fungus, the black spots indicate the more common phytophthora blight, according to Walter Schmidtke, nursery manager at Pesche’s Garden Center in DesPlaines.

Early in the spring, young emerging shoots may suddenly wilt and fall over, turn black and show masses of gray-brown botrytis spores. If nothing is done, these spores are carried to developing buds, which turn black.

Black spots on foliage, leaves turning red in summer, and black stripes on the stalk indicate phytophthora. “Plants with these conditions won’t have as much zest” said Schmidtke.

The best protection against recurrence of either blight is good sanitation. In fall, it is important to cut down and throw away all peony foliage, cutting stalks just below the surface of the ground.

If this doesn"t work and you resort to chemicals, the treatment is the same for both diseases. As soon as the shoots emerge in spring, begin spraying with Mancozeb, a copper sulphate solution, and repeat every 7-10 days until buds form, according to University of Illinois Extension. Spray the whole soil area for overwintering spores. In early summer you can spray plants with Daconil, a general purpose fungicide. Cut away any diseased foliage at once.


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questions

I have twelve beautiful blooming violet plants on my office desk, placed 12 inches from a light source that’s kept burning day and night. I water them from the bottom and let the water remain in the saucer.

No matter what I spray, I continue to have gnats and other insects in my soil. I also occasionally start to get yellow spots on the tips of the leaves and then the spots start going down the leaves. What’s going on here?

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?

We have a skylight in the bathroom over our Jacuzzi tub with an area around the tub that is quite large. What plants can we grow there, and what care do they need? Can we grow orchids?

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