Gardening with Gary

Gardening Advice from an Expert

Maple Trees

Q. Why does my variegated Maple Tree not have more of a color contrast? It has lost the white color. It is still variegated but with 2 different colors of green. It's about 4 years old and appears to be very healthy with a good amount of growth every year. PLEASE don't tell me it is reverting to one of the grafted types of trees. Is there anything I can do to help get the white back?

A. OK. I won't tell you it may be reverting! You can try something else...fertilizer. The white in any foliage comes from a lack of chlorophyll. If it were totally white, the plant would die, since it needs to make food from photosynthesis. But, many plants can survive with only parts of the leaves being green, other parts white, cream, yellow, pink or red.

Start giving the tree good shots of low nitrogen, high phosphorus food. On the container, read the label and look for the middle number of the three to be the highest, and the first number to be quite low. If you cut back on nitrogen, you have a good chance to bring out the missing pale color, or white.

It could be your soil and/or water pH is not suited to this maple. You can test both using a simple kit from a nursery and read what to do to adjust, so that the pH is lower and may assist production of white leaf portions. Let me know what happens.

Q. When can I prune the nonproductive branches from my maple tree?

A. Now [mid-May] is a good time to prune your maples of all weak or spindly poor growth to allow the other branches more light and nutrients from the roots. In fact, any bush or tree which is not blooming or about to bloom can be pruned.

Cari writes~
I have an autumn blaze maple tree that is approximately 4 or 5 years old. I bought it 2 years ago and have never pruned it. It is growing good but kind of spindly on the branches. When and how should I prune my tree for the maximum benefit?

A. You have chosen a remarkable fine maple hybrid, Autumn Blaze Maple Acer x freemanii (rubrum x saccharinum), which, due to its fast growth, requires pruning in the fall and the spring. Proper pruning, including taking out dead wood, weak branches and interior spindly growth to allow more sunlight penetration, is critical to the long-term health of all trees and resident safety.

In addition to clearing out deadwood and weakened limbs that could fall in a high wind or under the weight of ice and snow, twice-yearly pruning also helps to minimize damage from large trucks and reduces the possibility of injuries from low limbs or reduced visibility caused by streetlights obscured by poorly maintained trees. Winter pruning even helps prepare trees to better withstand next spring's inevitable onslaught of disease and insects. Shape your tree with strong branches outward and thin out extra smaller side shoots, plus of course any suckers or growth coming from the base or the lower trunk.

They have been planted in all soil types including heavy wet muck, fine loam and heavy clay, performing well in all soils. Autumn Blaze has better heat and drought tolerance than rubrum maples. The rapid growth rate (2-4 times faster than rubrum maples) allows Autumn Blaze to tolerate insect and disease problems such as leafhoppers and verticillium wilt that adversely affect some slower growing rubrum maples.

Autumn Blaze grows in a very uniform shape that makes pruning easy, either in production fields or the home landscape. The tree can be pruned into an upright shape or to form a broad spreading crown. Autumn Blaze also has excellent winter color. Rapid growth produces longer branching in one season than rubrum maples. This new growth retains good red color after leaf drop and persists until the following season, adding interest and color to the winter landscape. We feel that Autumn Blaze is a superior alternative to rubrum, Silver, Sugar or Norway maples.

Of the cultivars 'Armstrong,' 'Armstrong Two,' 'Autumn Blaze,' 'Indian Summer,' 'Marmo' and 'Scarlet Sentinel,' Autumn Blaze develops the best red to red-orange autumn coloration. Growth rate is approximately four times greater than Acer rubrum.  Leafhoppers have not disfigured this cultivar." -Professor Edward R. Hasselkus, University of Wisconsin-Madison, Department of Horticulture

"Autumn Blaze Maple is a recent introduction that lives up to its name, exhibiting brilliant and long lasting orange-red fall color. This widely adaptable tree appears to thrive in cold as well as hot areas, showing a remarkable tolerance for varying climates. It ranked among the best performers for growth and fall color display in the Southeastern US. This Acer freemanii hybrid deserves to be more widely planted as it combines the best characteristics of its parents, Red and Silver Maples." -J. Frank Schmidt & Son Co.

Autumn Blaze, a fast growing maple grows approximately 50' tall and 40' wide with a dense oval head and strong branching. It's beauty and resilience make it an excellent addition to any landscape. Using high rates of nitrogen fertilizer has proven to give amazing growth results and will also eliminate most of the splitting problems associated with maples due to verticillium wilt.

Selected 1997 Tree of the Year by the Iowa Nursery and Landscape Association
http://www.poplarfarms.com/autumnblaze2.htm

John writes~
I planted a autumn blaze this past April. It is about 8' tall and its trunk is about 3" thick. It is a very young tree. There are a few of these trees in this area that are at least double the size of my tree that are the brilliant red they are supposed to be! My tree is still green with some yellowing leaves and red spots on some. It is late October, so why didn't my tree turn brilliant red yet? Is my tree too young?

A. Autumn Blaze Maple (Acer X Freemanii) PP 4864, Zones: 3-8. Selected 1997 Tree of the Year by the Iowa Nursery and Landscape Association, the Autumn Blaze is an extremely fast-growing maple with brilliant red fall color. Under good conditions, it can grow 3' or more per year. It is tolerant of clay soils and drought. It grows 50' high and 40' wide. Trees do need to mature for the fall red color show. Less than six months is a short time in your yard. For the bright red fall leaf color, applying high rates of nitrogen will give amazing results plus will eliminate most of the splitting problems associated with maples due to verticillium wilt. This deciduous tree develops a dense oval head with strong branching which makes it a popular shade tree as well as an ornamental tree. Developed in North Central Ohio, Autumn Blaze Red Maple trees will grow in a wide range of climates from Michigan to Central Florida.