Growing Amur Maple (Acer ginnala)
Amur Maple (Acer ginnala) is an invasive species of plant that is native to the North-eastern part of the Asian continent. They are found in the far eastern part in Mongolia, Korea, Japan and in the Amur valley in Siberia. They are native to China and Japan.
As the title indicates, we will be looking into how to grow Amur Maple, both outdoors on a landscape and as a bonsai, but before getting into those details, we will look at what these Amur maples are and briefly their description. We will then move on to the section where we will be looking at how to grow these trees, the different requirements and how to maintain them.
To read more about the pests and diseases that affect the Amur maple, their uses, the different cultivars and some interesting facts, please follow the link below.
Did you know?
You can preserve the beauty of these beautiful Autumn leaves from the Amur Maple tree (Acer ginnala) or any other maple trees using Silica gel or a variety of other methods. Please have a look at the links below, they are really interesting and fun to do with the kids.
I hope you enjoy this interesting and beautiful fun filled art during the fall season.
Class – Magnoliopsida (Dicotyledons)
Family: Aceraceae (Maple family)
Species: Acer ginnala
Kingdom: Plantae (Plants)
Subkingdom – Tracheobionta (Vascular Plants)
Superdivision – Spermatophyta (Seed plants)
Division – Magnoliophyta (Flowering plants)
Also called Acer tataricum ginnala
Explanation of terms used:
Deciduous – plants shedding foliage at the end of the growing season
Perennial – a plant that lasts for three seasons or more
Panicles – branched cluster of flowers
Samaras – winged one seeded indehiscent fruit
Indehiscent - doesn’t open spontaneously at maturity to release seeds
Hardiness zone – a geographically defined area in which a specific category of plant life is capable of growing (please have a look at the U.S Department of Agriculture (USDA) Hardiness Zone Map to the right). This depends on climatic conditions and temperatures of the zone.
Stratify - exposing the seed to cold temperature for a period of time to break the dormancy
Iron chlorosis – Iron deficiency
Cultivars – A variety of plant developed from a natural species
Imbricate – Overlapping or layered
Serrate – toothed like saw
Hermaphrodites – having both male and female sexual characteristics
Stump – base part of a tree
Central leader - A central leader is when a tree has one main, centered trunk and this provides strength and stability
Soil pH level - pH is a measure of the soil's acidity or alkalinity. The scale goes from 1.0 to 14.0, with 7.0 being neutral
Acidic - having an excess of hydrogen atoms (having a pH of less than 7)
Alkaline soil - clay soils with high pH, poor soil structure and a low infiltration capacity
Mulch - a protective covering of rotting vegetable matter spread to reduce evaporation and soil erosion
Description of Amur Maple (Acer ginnala):
- Amur Maples are small deciduous shrubs or small trees that grow up to a height of 3 to 15 m (depending on how you prune and train them) and around the same width when mature with branches.
- Their trunks are around 20 to 40 cm in diameter with fine branches and leaves that can create dense shade. They can be grown to good shape with a dominant main branch and other smaller branches if pruned when young
- They have thin branches with thin barks that are greyish brown colour. The barks are smooth in young plants and then become fissured or vertically grooved as the plant matures.
- The leaves are opposite, simple leaves (see picture to the right) with 3 lobes each. The middle lobe is usually longer than the side lobes. The leaves are 4 to 10 cm long and 3 to 6 cm wide.
- The lobes have doubly serrated (toothed) margins. The upper surface of the leaf is glossy.
- During autumn (fall) season, the green leaves turn bright yellow, orange to red colour depending on trees and where they grow, with 3 to 5 cm long petioles (stalks of the leaf) that are mostly pink in colour
- The buds are imbricate buds and flowers of the Amur Maple tree are creamy white or light yellowish green colour that are 5 to 8 mm in diameter. They are produced during the spring season or in the month of May along with the leaves. The flowers are produced in panicles and are fragrant. The flowers are hermaphrodites.
- The fruits or seeds are paired reddish or reddish brown winged samara (some may be green samaras) that are 8 to 10 mm long with a wing of 1.5 to 2 cm. The fruits mature during late summer or early autumn.
- They have shallow fibrous root system
Characteristics of Amur Maple (Acer ginnala):
- The Amur maples are the most cold tolerant of all maples - USDA hardiness zone 3 to 8
- They are small trees that grow in areas where there is full sunlight or partial sunlight (shade tolerant) and thrive best in moist well-drained soil although they are tolerant to dry soil.
- They grow very slowly
- They tolerate alkaline soil and do not tolerate salinity. They grow well in soil with pH from 6.1 to 7.5
- They lose their leaves every year during fall season and then new leaves grow back during the spring season.
How to grow Amur Maple (Acer ginnala)?
There are different methods that can be used to grow an Amur Maple tree.
To grow Amur Maple from seeds, you need to harvest the seeds when they are fully mature. Do not let them dry and produce any germination inhibitors (substances that retard or stop the germination activity). Choose fresh seeds
Prepare the seeds by soaking in water for a day or two (24 to 48 hours) and then stratifying (keep in the refrigerator at a cool temperature) the seeds for a few months (one to four months) at 1 to 8 degree Celsius in a zip-locked bag. The seeds would have started to sprout by now.
Note: Seeds collected during October or November, should be ready to be sown the following March or April
Sow these seeds in a seedbed and make sure that it is spring or early summer, with no frost. They should sprout completely in 2 to 4 weeks depending on the temperature. It is best to have them in a warm place with partial sunlight and keep the soil moist (do not over water).
If not soaked or stratified, these seeds germinate only after a year after which they can be transferred to a nursery bed. Make sure that the seeds are fully mature, as immature seeds will either not germinate or will produce very weak plants. Also maples that grow from seed are necessarily not true form (this could be due to cross pollination)of the parent tree.
Note: Trees that grow from seeds grow very slowly and have low vigour compared to trees grown from cuttings.
In order to get a true to type tree that has the same characteristics of the main tree, you can grow the Amur Maple from cuttings. Young healthy shoots of the tree that have 2 or 3 pairs of leaves and one pair of buds on the base should be cut during June or July. Seal the cuttings in a plastic bag to prevent moisture loss and make sure that the shoots do not wilt.
Trim the cutting, removing the lower leaves but with three to four pairs at the top. If required you can apply rooting hormone to the cutting to improve rooting. Insert the cuttings into the rooting medium where the cuttings root within two to three weeks after which they can be potted.
From a nursery or garden centre:
If you have bought an Amur Maple from a nursery or plant dealer or garden centre that come in containers, you should wait for the tree to be at least 20 cm tall before which you should not plant it permanently in the soil. This applies to trees grown by all the above methods.
The Amur Maple as you can see from the characteristics above, are tolerant to moist and dry soils and you need to keep a check on the acidic or alkaline levels in the soil as highly alkaline soils can cause the tree to develop iron chlorosis.
How to grow Amur Maple (Acer ginnala) as bonsai?
Amur Maples do well as bonsai and Durand’s dwarf is the best cultivar to grow as a bonsai. These can thrive in zones 3 to 8. The bonsai need watering regularly during summer heat (sometimes 2 to 3 times a day to avoid drying of leaves) and less during winter.
How to Repot Bonsai Trees - The Basics
Bonsai can be grown either from seeds or cuttings using the methods above. When the trees are young and mature enough with a few branches, you can prune them to the desired shape. The best time for pruning is early spring when the buds form. Amur maples can be cut close to the bark and shoots that are around 6 cm can be trimmed to maintain the dwarf size of the plant.
The bonsai need to be fed weekly during the first month after leafing and then after every two weeks. You can use bonsai fertilizer or half strength plant food. Since these species bud well on old wood, they can be cut back quite hard and the leaves can be defoliated every two years during mid-summer. Any new shoots that grow should be pruned.
Pinch off large leaves all through the growing season. The soils to be used are clay, loam, sand, acidic, alkaline, well drained soils, bearing in mind the pH levels.
Repotting should be done in early spring before buds come out. Young trees need repotting every year initially, and later the trees need repotting every two years. Mature older trees can be repotted every 4 to 5 years, but it is best not to have the older trees bare-rooted.
Care should be taken not to re-pot on the same year when you defoliate. You can wire the tree to get desired shapes, but that requires protection of the bark. You can wire the tree when it is dormant in Autumn after the fall and then use a wrap to protect the bark. Do not leave the wire for longer periods of time as it will scar the bark.
To plant Amur Maple (Acer ginnala) permanently in the soil:
The plant that is ready to be planted into a permanent position into the soil will either be one that was bought from the nursery or one that you grew yourself. Make sure that the plant is mature enough to go into that soil.
- So before planting Amur Maple, you need to choose a place that has acidic or neutral pH soil and full sun or partial shade. Make sure that the soil is able to retain moisture and able to drain well.
- The tree should be planted around 2 feet deep and wide dug holes in a medium coarse soil. Mix the dug out soil with some compost or peat moss to enrich the soil.
- Remove the plant from the container by tapping to loosen the soil.
- After removing the plant from the container, set the plant in the dug hole. Slightly and gently loosen the roots with your fingers if they are tightly packed. If the rootball is wrapped in jute fabric (in case of nursery bought plants), it must be removed along with any strings or wires that secure it as otherwise these will hinder the roots from growing freely into the soil.
- Now fill the hole with the soil to which you have added compost and pack it firmly around the root ball. Fill soil to the level of the plant from where roots begin to branch out from the main stem.
- Water the plant and lay some mulch at least 10 cm away from the main trunk or stem of the plant to retain moisture.
Interesting methods to preserve maple leaves!
- The plants need water depending on the season, and deep watering is advised as it helps the roots grow deeper and makes the plant sturdier and drought resistant
- Check moisture level in soils with your finger, if no moisture up to a depth of 2 to 4 inches, then it needs watering.
- The new plants need to be monitored this way for at least two years after which they will be big enough to survive on their own.
- They should be pruned in Winter or early Spring for them to develop into good shape.
- The Amur Maple trees when young, if they receive the required amount of water and fertilizers, will grow quickly and healthily.
- The trees should be fertilised once every 2 or 3 years during the early Spring season when they begin to bud.
- Fertilisers are available in different forms like, granules, slow-release, liquid feeds, organic or synthetic.Choose the best one for the type of plant, whether tree or shrub. Also follow the instructions on the packaging for amount to be applied and frequency of application, otherwise it can injure the plant.
- You can also go for the nutritionally balanced, 10-10-10 (They are stable, well-balanced fertilizers and will give your plants or trees most of what they need).
- The pruning process varies for different plants or trees depending on their size and shape, but all plants need dead branches removed to enhance healthy and dense growth of the plant with more flowers and leaves.
- You can train the tree as it grows according to your need by pruning to a small tree or a tall shrub
- Make sure you use sharp and clean tools to prune otherwise it can lead to damage and infections.
- Dead branches should be removed close to the trunk along with the bark. Pruning other branches should be done above a leaf bud at a slight angle. New branches sprout from the bud below the cut.
- Some shrubs can be sheared to form hedges
- Tools like hand shears, pruners and loppers are used for shrubs and pole pruners and saws are used for big trees.
- If you feel that you cannot safely prune a tree, please call for a professional pruner to do the job.
Requirements to grow Amur Maple (Acer ginnala):
- For a healthy start to the plant or tree, it is best to plant them during spring or early fall season
- Do not plant them crowded together, so choose places where they have space to spread the branches and for free rooting
- Plant the trees away from walls, decks, building foundations in order for them to not block windows, roofs or power lines.
- Leave at least 10 feet between trees to prevent overcrowding.
How to maintain the Amur Maple (Acer ginnala)?
- Prune the Amur maple according to your interests. If you wish to have a single trunk choose a central leader, then prune and train the tree accordingly during winter, cutting off side branches.
- If you need a multi-stemmed shrub then leave the lower branches on while pruning and prune the top layers.
- They grow well in regions that have a cool summer, however they can grow in warm regions as long as the plant or tree is watered well and not let to be dehydrated.
Now like other trees and plants, the amur maple is also prone to pests and diseases. Also they have various uses, cultivars and some interesting facts. Please follow the link below to read more about these maple trees.
You may also be interested in some creative work with the Amur maple leaves!!!
You can preserve these beautiful Autumn leaves from the Amur Maple tree (Acer ginnala) or any other maple tree using Silica gel or a variety of other methods. Please have a look at the links below, they are really interesting and fun to do with the kids.
I hope you enjoy this interesting and beautiful fun filled art during the fall season.
I would appreciate your thoughts, ideas, experiences and feedback on this hub. The information provided here are after a thorough research through various sources. This is not an advice from an expert, but general information on how to grow the Amur maple trees.
Thank you for stopping by. I hope you enjoyed reading.