Growing Shantung Maples
Finally, a colorful maple for the texas sun and soils!
Shantung maples are easy to grow. They are shade trees that like full sun to a half day sun but will even survive in shade. They seem to like slightly acidic sandy soils the best, but will grow quite well in heavy clay or alkaline soils. Shantung maples do not like being too wet. I let mine dry out between watering. In the hot dry climate of North Texas your Shantung maple should live well over 100 years unless it is planted in an area that restricts root growth, such as a small courtyard or very small yard surrounded by foundation, driveway, or roads which may shorten its life expectancy. The basic growing plan is to give them sun, lots of soil to grow in, consistent but not too often deep watering, and then just standing back and watching them grow.
Shantung maples grow every day. Even in winter they are growing roots when it's above forty degrees. To get fast growth they need sun, moisture, oxygen, carbon dioxide, and all 13 plant nutrients on a balanced and continuous basis. Maximum growth will not be achieved if any of the nutrients are in short supply. North Texas soils are usually only low in nitrogen but use of complete fertilizers will give your tree a more balanced nutrient availability. A soil test is the best way to reveal shortages. What may look like nutrient deficiencies are usually the result of other problems like poor drainage, herbicide damage, soil compaction, root fungus, or from inconsistent moisture levels. Over-watering may leach nitrogen and other nutrients from your soil, or produce a weaker root system which makes it harder for the tree to deal with extreme weather conditions when they arise.
Metro Maples is a leader in Shantung and has tested them in every way. In the year 2006 the neglected Shantung out by Dick Price Road got permanent wilt from a two year drought. Permanent wilt means that even after watering the leaves were still wilting the next morning. It took over 2 weeks before the tree recovered, so be patient. Even as dry as it got, it did not lose any leaves or branches and it was as beautiful as ever in the fall (see picture under Shantung Maples, it is the close-up of yellow fall color). I do not suggest you let your Shantung get that dry as it probably was getting close to being seriously damaged.
Large trees in your yard are irreplaceable, so make sure they get water during droughts. Annuals, perennials, and even shrubs can be replaced, but mature trees might take 2 generations to replace! Large trees help to cool your house, saving you energy, and if you choose one like the Shantung maple it will cool your yard and enable you to use less water on your shrubs and lawn. My yard is about 10 degrees cooler than the neighbors treeless property. St. Augustine grass takes much less water in the shade. The best way to water is deeply and not too often. I find it takes me 3 to 5 hours from a single Rainbird shrub head to water a 20 foot tree in totally dry soil, which is about 500 gallons of water, but it might not get watered again for 2 weeks. Shantung maples are great street trees and can be planted 8 feet from your house. I do not think Shantung roots will tear-up a patio or sidewalk.
Most soils have enough nutrients although adding a complete fertilizer will improve growth. Good times for adding nitrogen are early March, and again in early May and September when it cools-off. Temperatures and timing of fertilizer and water are everything to achieve maximum growth potential. Do not fertilize them in summer. Shantung are sensitive to nutrient imbalance so be careful when adding just one nutrient as deficiencies or toxicities will result. Also, remember never to fertilize a tree that is damaged or overly-stressed, but wait until the following year. Damaged trees for whatever reason will not usually look or act normal until the following year.
Shantung benefit from consistent watering until they are established, or during droughts, but too often people over water them the first year. Do not water them every day unless you have planted it at the wrong time like in summer or early summer! Once every 5 days between watering is plenty even with very high temperatures. Once established in one or two years, they like consistency, either once a week, bi-weekly, or longer between watering. Stressed trees do worse when continued to be over-watered and can lead to death. You know your tree is stressed if it losses its dark green color or has some burnt edges. Keep them mulched and do not allow root competition from other plants in their root zone until they are established. Getting rapid shoot growth the first year in the ground may not be possible without rainy periods or a knowledge of fertilizing basics, but be assured that it is growing lots of roots getting ready for fast growth the next year. Wrapping the trunk prevents damage to young bark from the sun and weed-eaters.
Dig a wide hole to break-up the soil which will help the roots to quickly grow out. Add some organic matter, sand and compost to a depth of 15 inches if your soil is workable or just use your native soil. Do not plant too deep.When the trunk at the base starts to increasingly widen, this is your soil level point. Young trees do not always have a noticeable root flare or may have just one large root. With age your Shantung will have many large roots all around the trunk base. I have never seen or heard of a Shantung maple having trouble with circling roots. They should not require staking. I have planted a Shantung maple in a very windy spot in a sandy soil and while it is leaning a little away from the wind it has been fine. Growth will be thicker and slower in windy locations. Shantung maples have many fibrous roots, primarily within the drip line. Replace washed-out soil that exposes roots around the base, as they will burn when exposed to the sun.
Shantung maples will look better if pruned at a young age. This maple has a tendency to grow very low branches and trunks. Prune-off low limbs, that are small, up to where bigger main branches start, around 3 or 4 feet is nice. Smaller branches below larger branches will not ever grow as fast and will stay smaller, and I feel that the first branches on a tree should be the largest ones for the best look. Remove any small weeping branches that hang down to enable you to get close to your tree and for a cleaner look.
The natural shape produces many crowded branches with many leaders. Major pruning can be done right after leaf drop in December or again in early May/June. One inch branches pruned on a vigorous tree will be completely healed-over by the end of summer. I wouldn't worry about painting the cut unless the tree is under some kind of stress. If you prune at the wrong time and get excessive sap flow don't worry. In about 9 days the wound will be sealed enough to stop the sap flow.
Don't prune your Shantung Maple up too high too soon. At least two-thirds of the height of the tree should have branches. Far too often I am seeing elms, oaks, etc. that are being pruned way-off the ground leaving very little branches, and leaves, for photosynthesis. It is way too much shock for a tree at one time. Do not prune lower limbs on very old trees. Recently someone in Mansfield pruned-off all the huge old lower limbs on an old cemetary oak that will never heal over and will eventually result in the tree's death. Don't let anyone prune your tree without first making them mark the branches, showing you what they will do.
Be careful of weed killers around your trees. Shantung have been killed by the product Image and other weed killers. Also be careful of using any foliar sprays when temperatures are above 80 degrees as damage may result from heat induced phytotoxicity.
Lastly, be careful not to scratch the young bark on the trunk or branches. Small wounds are not a big health problem but when the tree turns that area naturally black, as if painted, it can be unsightly. Don't let cats use your tree as a scratching post as it will leave black marks for several years.
Plant Shantung maples at the proper time for our 1 year guarantee. We no longer guarantee trees planted in the months of May thru mid-September as this can be too stressful for them in our hot climate if not watered properly.