I plan on saving my amaryllis bulbs that I kept outside over summer, but I noticed red streaks on the inner side of the leaves. What caused that? Will I be able to save my bulbs?
There are several possible causes of red streaks in amaryllis hybrids (Hippeastrum), explains Bill Welter, owner of Victor Hlavacek Florist, Winnetk. If the streaks occur on the foliage only, excess moisture and not enough air around the bulb could have caused the streaks. Amaryllis is also susceptible to leaf scorch, which can cause red streaks on the foliage and on the bulb. This was common on older varieties.
You can save the bulb for next season by letting the leaves die down, then trimming off the foliage, and dipping the bulb in a fungicide solution. Another possible reason for leaf scorch is tobacco mosaic disease, transmitted by insects.
My Siberian iris ‘Gracilis’ plants have only one bloom per clump. I have five 3 to 5 year-old clumps that are 8 to 10 inches wide. They do not appear to be crowded. All are planted in a moist area. Why is there only one bloom per clump?
“Iris bloom is directly proportional to the amount of sun received,” proclaimed Chuck Simon, Hinsdale, past president of the Northern Illinois Iris Society, who grows 10,000 rhizomes of 1,000 to 1,500 iris varieties. Iris need 4 to 5 hours of sun, but full sun is best. Another cause of bloom failure could be iris borers, which eat mature fans and cause only minor increases in plant growth. Spray with Cygon 2E in spring when eggs of borers hatch in order to break their life cycle. When transplanting iris, make sure the roots remain moist. Grow them in moist but not wet soil. In the first year after planting, water them religiously. Once past that point, they are very hardy. Simon, a master iris judge, referred to the American Iris Society checklist for any special cultural conditions affecting bloom and discovered that this variety is very old. Iris siberica ‘Gracilis’ was introduced in 1927.
I have lost four 12-15 foot tall white pine trees over the last year. All had the same symptoms, browning needles at the bottom that continued up to the top. Can you tell me what pest is killing the white pines? I am also losing an Austrian pine now. It is experiencing the same symptoms.
White pines in this area are very rarely troubled by disease. They are, unfortunately, highly susceptible to high pH problems, or soil alkalinity, and are utterly intolerant of salt, according to Rich Eyre of Foxwillow Pines, Woodstock. The browning needles could also indicate the plant is getting too much water or has poor drainage.If environmental problems are not the issue for your white pines, consult an expert. Betty Lockwood, Plant Information Specialist at the Chicago Botanic Garden, suggested you bring them a sample branch to check on disease and bring in an arborist for an on site visit to check your growing conditions. Or take a 12-inch sample of an affected tree to your local extension office.Austrian pine is very tolerant of environmental conditions but is prone to certain diseases—diplodia tip blight and dothistroma needle blight, both caused by a fungus. Only an arborist or a laboratory can provide an accurate diagnosis. If you bring in a 12-inch sample for diagnosis, be sure to sterilize your pruning shears with denatured alcohol after cutting the diseased wood.
What is the best way to dig up, clean and store gladiolus and dahlias? What are the little white sacs on glad bulbs?
Gladiolus corms and dahlia tubers are generally dug up after the first frost or before Halloween. Cut off all the stems and foliage, let the plants dry, and shake off all the soil. Make sure each corm and tuber is firm and not rotted. Place them in a box or tray and cover with peat moss. If you know the cultivar name, tag the plant.
Store them in a dark, cool place, checking them over winter. If the dahlia tubers are shriveled, sprinkle a little water on them. Dahlias can be potted up in spring for an early start in the garden.
“The white sacs you see attached to the gladiolus corms are little bulblets. You can remove them or not. If left on the corm, they will grow larger, and may enhance the number of stems on the plant. If you remove them and plant them, it will take at least three years before they flower,” explains Joni Cotton, perennial manager, Hawthorn Gardens, Hawthorn Woods.
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.”
I have some peonies that I want to transplant but cannot plant them in their permanent place until next spring when our new house will be built. Can I dig them now and transplant them again next spring?
The correct time for transplanting herbaceous peonies is late September into October. Cut back the foliage when you dig them up. Each clump you move should have at least three eyes, or growth buds, and thick tuberous roots. Dig a hole deep enough to cover the eyes with two inches of soil when you transplant. If planted too deeply, they will not bloom.
Transplant the peony into its temporary place, or else move it into a container and dig the container into a shady area, not in full sun. Be careful about watering the container plant; try to keep it evenly moist. Next spring, move the peony into its permanent location, suggests David Leider, perennial grower at Klehm Plants, Barrington.
“Replanting in spring disrupts the roots and will halt blooming for one year. Peonies are pretty strong plants and very hardy. They will recover,” says Charlotte Thayer, assistant to the owner at The Natural Garden, St. Charles.
What is the largest tree that one can plant? We are trying to replace some 7- to 8-foot trees that were recently destroyed.
Trees sold at garden centers that are 2.5 to 3 feet tall, with a 2.5 inch diameter trunk, can be planted by hand. A hole for a ‘balled and burlap’ tree with a 5 to 6-inch diameter trunk can be dug by hand without a tree spade.
Any tree with a trunk larger than 6 inches in diameter would need a tree spade to do the moving and digging. Even large trees, such as a 35-foot tall tree with a trunk 9 or 10 inches in diameter can be transplanted with proper equipment. “Spruces 30 feet tall can be installed easily with a tree spade,” according to Greg Oltman, owner, Gro Horticultural Enterprises, Huntley.
I recently moved to Chicago from Houston and I miss fresh picked figs. Is there any way to grow figs in Chicago short of installing a greenhouse? Will sunny windows do? I’m desperate.
Figs (Ficus carica) are handsome plants with smooth gray bark and large lobed leaves which can grow into gnarled trees in warm climates. In Illinois, with winter die-back, they are grown as shrubs. They should be sited where they get some protection from the wind in winter.
You do not need a greenhouse to grow figs, and a sunny window would not be appropriate. Grow a fig cultivar suitable for this climate. While most figs are rated to winter hardiness zone 4, the problem comes because our growing season is too short to ripen fruit, which may take until September or October in a cool summer. Sometimes we have an early frost. If so, pick unripened figs and let them ripen in the house.
Alana Mezo, senior horticulturist for the fruit and vegetable island at the Chicago Botanic Garden, recommends ‘Chicago Hardy’ fig, the variety they grow. They have 10 or 12 plants there growing in a row and, through trial and error, have decided not to protect them over winter because rodents chew roots and stems in wrapped plants and set back their growth. Their figs are multi-stemmed, die back to the ground when unprotected, and get off to a slow start in the spring, delaying fruiting.
However, if you do not have a rodent problem, tie the stems together, wrap burlap around the tied stems, and cover the base with a basketful of leaves. With this protection, your plants will have a head start in spring, and you should have figs ripen a month earlier than unprotected plants, at least by late August.
Another method of winter protection is to root prune in a half semi-circle around the plant, lay it down and cover the plants with leaves over winter.
If you grow a fig in a large container, you can wheel it into an unheated garage and store it over winter. Watch it to see if it needs moisture. Your plant does need a dormant cold period, but not a freeze. This is an “iffy” process according to Mezo.
A fig grower in Highwood claims that rubbing olive oil on the fig hastens ripening, but Mezo has not tried this yet.
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.
Besides mums, what are a few other plants you would recommend for containers for fall color?
Dwarf or miniature sunflowers add a bright, sunny pop of color to any container. Mix them with pink celosia, ornamental kale, dwarf ornamental grass and ornamental peppers for a special autumn arrangement. The kale is a great addition as the colors get brighter with colder temperatures. Ornamental pepper can also be taken in and kept as a houseplant through the winter months. Or use aster through October and plant in the garden before the soil freezes. Comes in many colors.
The rudbeckias ‘Indian Summer’, ‘Prairie Sun’ and ‘Becky Cinnamon Bicolor’ all have beautiful large flowers. Herbs and leafy vegetables like Swiss chard ‘Bright Lights’, mustard ‘Red Giant’, bronze-leaved fennel and variegated sage all add fun textures. Plectranthus ‘Mona Lavender’ combines nicely with ornamental kale and cabbage. Also plant trailing pansies like those in the ‘Cool Wave’ series at the edge of planters and hanging baskets. Another creative way to add interest to fall planters is with preserved and dried botanicals, sticks or accents.
Our favorite addition to autumn containers – hands down – is ornamental kale. As the temperatures drop, the leaf color intensifies and the plant actually becomes more attractive. We frequently pair ornamental kale with late season grasses as well as decorative gourds and squash tucked amongst the foliage to celebrate the abundance of the harvest season. Your visitors may still be enjoying your kale peeking through the early snow on Thanksgiving Day!
What causes black spots on my orchid leaves?
I’d like to plant a white bark birch in front of my home in my sunny front yard. What can you tell me about Betula utilis var. Jacquemontii?
I received a beautiful flowering azalea plant during the holidays. I would like to continue growing it over winter. Will I be able to bring it into bloom next year?