Osmocote Advertisement

Hydrangeas

When is the best time to cut back hydrangeas? How far do I cut them back?

Pruning hydrangeas depends on the species. Oakleaf hydrangea (H. quercifolia) and Peegee hydrangea (H. paniculata), with its well-known cultivars ‘Limelight’ ‘Little Lamb’ and ‘Tardiva’, are woody shrubs that bloom on old wood. Trim them within two to three weeks after flowering. The following year’s primary flower buds form near the top of the stems in late summer. If you wait too long to prune, you will be cutting off flowers on the old stems.

The new bigleaf hydrangea (H. macrophylla) ‘Endless Summer’ is an herbaceous plant that dies to the ground over winter and starts into new growth in spring. It can be cut at any time since it flowers on both old and new wood.

Hydrangea ‘Annabelle’ (H. arborescens) can be trimmed at any time. “It dies back totally to the ground each year so you can keep it trimmed to the size you want,” says Jean Bragdon, garden center manager at Lurvey’s Garden Center, Des Plaines.


Japanese Maple

I’m moving to a townhouse with limited direct sunlight. I would like to put a Japanese maple in a north-facing garden but don’t know if it will do well. What are the best kinds? Also, when is the best time to plant a small tree?

Japanese maples are small decorative trees which are becoming more popular as more dependable cultivars come on the market. Even so, an established tree will sometimes succumb in a severe winter. Their light requirements vary.

The trees can grow in a northeast exposure, and 6 hours of sunlight is not too much, according to Jeff Sibley, nursery manager of Red’s Garden Center, Northbrook. They need a moist, well drained, neutral soil, amended with organic matter. They can grow to 8 feet tall in a good location. He says the best planting time is right after Mother’s Day. A protected spot and plenty of moisture are critical elements for survival, even with the newer cultivars.

Sibley recommended the following cultivars of Acer palmatum var. dissectum, a cut-leaf variety, as the most graceful trees:

  • ‘Crimson Queen’ is a small shrubby tree, with finely cut reddish leaves that hold color all summer and turn scarlet before dropping off in the fall.‘Garnet’ is similar to ‘Crimson Queen’ but a somewhat more vigorous grower.‘Bloodgood’ is a vigorous, upright tree with blackish red bark. It has deep red spring and summer foliage, scarlet in the fall.
  • Acer palmatum var. dissectum ‘Viridis’ Lace Leaf Japanese Maple is a small shrub with drooping branches, green bark and pale green, finely divided leaves that turn gold in autumn. It takes shade.

Ground Cover Suggestions

I have a dampish area with poor grass and moss that I would like to change to ground cover, but if I have only one plant, won’t it be boring? Can I get rid of the grass in winter or early spring?

If we have a dry winter or spring, you can smother the grass with a heavy layer of newspapers held down by bricks or stones, or use a product that will kill the grass. Use it according to the label directions. Grass roots are very persistent, so you may have to dig out the remaining roots by hand. The moss will disappear as you aerate the soil and rake in organic material.

When your area is properly prepared, you will have a large choice of low-growing groundcovers.

Kim Schroeder, perennial buyer at Wasco Nursery and Garden Center, St. Charles, suggests the following: lily of the valley (Convallaria majalis), sweet woodruff (Galium odoratum), wild ginger (Asarum canadense), or European ginger (A. europaeum), vinca (Vinca minor), Tiarella, Astilbe-the cultivar ‘Perkio’ is shorter than Astilbe chinensis ‘Pumila’ and violas such as bird’s foot viola (Viola pedata) or sweet white viola (V. blanda).

These choices are not aggressive growers like goutweed (Aegopodium), which grows anywhere and is very difficult to eradicate. You can plant free form areas with one type and another alongside it as contrast. Most of these ground covers bloom at slightly different times to give you a spring-into-summer flowering season.


Pumpkins

I’d like to know the secret to growing a decent-sized pumpkin for jack-o-lanterns for the grandkids and for decorating. My experience in recent years is that they get about as big as a basketball and then begin to rot. What am I doing wrong?

The longer the fruit is on the vine, the greater the chance it will rot. By September its size is apparent, and it turns orange. It is best to plant pumpkins in different soil each year or every two years, according to Sue Murdock, manager, Goebbert’s Pumpkin Farm, South Barrington.

The size and use of pumpkins is determined by the seed you buy. ‘Atlantic Giant’ produces fruits that weigh hundreds of pounds. A better choice is to grow ‘Howden’. It bears well-shaped 10 to 20-pound fruits, the perfect size for jack-o-lanterns. ‘New England Pie’ is the standard for pies with smooth, bright orange flesh. ‘Wee-B-Little’ is a miniature round pumpkin bearing 3- to 4-inch fruit useful for table decorations and suitable for tiny hands.


Types of Fruit Trees

I am going to be planting five dwarf fruit trees; two ‘Bartlett’ pears, one ‘Cresthaven’ peach, and two ‘Honeycrisp’ apples. Could you give me some feedback on them?

If you buy young container fruit trees, plant them very early in the spring to lessen transplanting shock (as soon as the soil can be worked and before the buds break). Plant the tree at the level it was in the pot, adding a layer of top mulch.

“Wrap the trunk in paper or plastic tree wrap to prevent deer and rabbit damage. Protect the trunk from voles with fine wire mesh at the base,” says Tim Norris, president of Spring Bluff nursery, Sugar Grove.

‘Bartlett’ pear is subject to fire blight and also needs a pollinator for good fruit production. ‘Patten’ and ‘Parker’ are two pear cultivars Norris recommends. Two different cultivars will give you better cross-pollination.

‘Honeycrisp’ apples are an excellent choice for this area. They grow up to 20 feet tall on semi-dwarf root stock. They can be pollinated by any member of the Malus family, including a nearby flowering crab tree.

‘Cresthaven’ peach, while hardy here, may not bear fruit, depending on how cold the winters are. When the temperature goes down to zero, ‘Cresthaven’ peach loses all its flower buds. Norris suggests growing ‘Reliance’ peach instead. It needs a long growing season. Last spring (2008) was a cool one and peaches did not bear much fruit. Peaches are not long-lived trees. By the time the tree is bearing fruit, you will need to start growing another tree.


Planting Tulips

Is there a best time to plant tulips? I see them at the garden centers in late summer but I am afraid that it is too early to plant them. If I wait too long, I might forget all about them.

Fall bulb planting should wait until soil temperatures drop to 55 degrees or cooler. This usually occurs when nighttime temperatures drop to 50 degrees or lower for two weeks or more. While waiting to plant, store the tulips in a cool, dark place away from direct sunlight—but don’t forget them. After planting, water the bulbs well, advises the Netherlands Flower Bulb Information Center.

If you plant grape hyacinth bulbs amidst your tulips, they will come up early in the fall and serve to mark the position of your tulips.


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.


Azalea

We moved into a house with a lovely azalea that didn’t bloom. We thought it might have been over-pruned. Last fall we did not prune it and now it still hasn’t bloomed. I was hoping to transplant it this year, but it looks rather sickly. Shall we prune it again and give it another year? Can I still transplant it?

Stop pruning your plant since you may have over-pruned it. Evergreen azaleas only need tip pruning in July after their flowers have faded.

Concentrate now on rebuilding the azalea into a healthy plant. Do not transplant a sickly one. Feed your plant regularly with an liquid acidic fertilizer. Keep your plant weeded and its roots moist by using mulch because azaleas are surface rooters. Make sure your plant is situated in soil with good drainage and in a part sun/part shade location.

Try this regime over summer and evaluate your plant next spring, advises Charlene Wooten, manager, Cedar Hill Nursery, Lake Zurich.


Low Light House Plants

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?

Use plants that grow in low light such as pothos, philodendron, peace lily (Spathiphyllum), Chinese evergreen (Aglaonema), any type of dracaena, and include lady palm (Rhapis) for height. It would be possible to grow moth orchids (Phalaenopsis).

“While the bathroom will give you good humidity, your plants must be watered thoroughly. The peace lily needs to be kept evenly moist. Feed monthly with an all-purpose houseplant fertilizer,” advises Elizabeth Hoffman, manager, West End Florist, Evanston.


Winter Mulch

Must I mulch my garden and, if so, when is the best time to apply it? What are the best materials to use?

Perennial gardens usually come through the winter better when given some sort of protection, although many gardeners leave their established gardens unprotected save for deer netting to keep deer off newly emerging greens in spring. Plants new to your garden can be protected by mulch during the first winter and may not need it after that.

Mulch is used in winter not to keep the plants warm, but to keep the ground at an even temperature and prevent plants from heaving out of the soil during periods of alternate freezing and thawing. Thus it is applied after the ground freezes. If mulch is applied before the ground freezes, it can smother the plants.

The simplest mulch is a loose layer of oak leaves, which do not mat down and rot. Ground-up leaves are ideal, and even dried grass can be used. Or apply straw left over from Halloween decorating.

Use only a few inches of mulch and keep it light enough not to smother the plants. Deer netting helps to hold mulch in place until it is wet enough not to blow around. In spring, as soon as the plant starts to grow, remove the mulch gradually, a little at a time over several days. Don’t wait too long because if the shoots are too tall, you may damage them as you pull off the mulch. Work the mulch into the soil with a trowel afterwards.

Heucheras, astrantias and recently planted perennials may heave even if mulched. Push any dislodged plants back into the soil. Mulch also protects the evergreen rosettes of biennial hollyhock, foxglove, Canterbury bells and sweet William from snow and ice damage.


Page 6 of 8 pages ‹ First  < 4 5 6 7 8 > 

categories

popular

questions

I have a cycas palm and am not sure how much direct sunlight or water it needs. It has light brown marks developing on the leaves. What is causing this, and how do I care for my plant?

Must I mulch my garden and, if so, when is the best time to apply it? What are the best materials to use?

How do I renew my subscription?

ChicagolandGardening Advertisement