Tim talks about leaving your Japanese Maples outside in pots all winter on this episode of the MrMaple Show.
Japanese maples are stunning ornamental trees, with intricate leaf shapes and striking colors. Many gardeners choose to grow them in containers so they can showcase their beauty on patios and decks. But how should you care for potted Japanese maples during harsh winter months? Proper overwintering is key to their health.
In this article, we’ll explore best practices for protecting your potted maples when the weather turns cold.
Why Winter Care is Crucial
Japanese maples are originally from temperate Asian regions with cooler winters, But the roots of potted trees are more exposed than those planted in the ground This makes their roots vulnerable to potential freeze damage,
If you live in an area with extremely cold winter temps below 10°F, the roots can freeze and die back. And even where it’s slightly warmer, pots offer little insulation to protect roots from hard frosts.
Wind and sun exposure through winter can also dry out above-ground branches. Plus, maple bark and twigs are prone to sunscald without adequate winter protection.
That’s why some extra care is needed to help potted maples survive until spring
Watering Potted Maples in Winter
Moisture management is important for winterized potted plants. Here are tips on winter watering for container maples:
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Before dormancy – Deeply water trees in late fall before the ground freezes. This ensures they hydrate before going dormant.
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During dormancy – Water sparingly, only if soil is fully dry. Goal is to prevent roots from drying out, not stimulate growth.
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Late winter – Monitor closely and water lightly as needed in late winter. Don’t allow pots to dry out as temps warm.
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Indoor maples – Potted maples kept indoors likely need more frequent watering in winter than outdoor ones.
The key is not to overwater – soggy soil leads to root rot in cool weather. But don’t underwater either. Find the right balance through careful monitoring.
Protecting Roots of Outdoor Potted Maples
For potted Japanese maples left outdoors, extra protection of the containerized roots is advised:
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Situate pots in a sheltered area out of wind. Grup pots together for insulation.
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Surround pots with mulch, leaves, straw or other organic material to insulate roots.
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For extreme cold, wrap potted maples with burlap or place entire pot in a larger container filled with mulch.
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Move potted maples into an unheated garage or cellar if temps drop below 10°F for extended periods.
Take steps to prevent roots from freezing or fluctuating in temperature too drastically from day to night.
Safeguarding Branches of Outdoor Maples
In addition to vulnerable roots, exposed branches of potted maples need protection from winter extremes:
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Avoid sites with direct sun exposure which can burn bark and twigs.
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If possible, move pots under eaves or cover with burlap to shield from wind.
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Wrap trunks of very young trees to prevent sunscald damage.
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Prune any dead or damaged branches in early spring after reviewing winter dieback.
Shielding branches from harsh elements preserves the beautiful form of Japanese maples.
Transitioning Maples Back Outside
For potted maples moved into shelter for winter, reacclimate them slowly back outside in spring:
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After final frost date, set pots in a shady spot for a few days, then gradually increase sun exposure.
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Watch for new growth emerging and be ready to move indoors if a late cold snap occurs.
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When nighttime temps stay above freezing, maples can remain outside.
Prevent shock by transitioning dormant indoor maples to spring conditions incrementally.
Fertilizing Potted Maples in Spring
Spring growth requires nutrients. Fertilize outdoor potted maples as weather warms:
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Wait until soil thaws and new buds swell. Never fertilize dormant trees.
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Use a balanced granular organic fertilizer formulated for containers. Follow label rates.
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Alternatively, use a liquid kelp or fish emulsion fertilizer every 2-3 weeks per label instructions.
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Discontinue fertilizer by early summer to harden off tree for next winter.
Avoid over-fertilizing container maples or forcing lush growth late in season – this makes trees prone to winter damage. Cease fertilizing midsummer.
Pruning Maples After Winter
In early spring, prune potted maples to:
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Remove any dead branches damaged by winter winds or sunburn.
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Eliminate crossing branches to improve form and structure.
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Control size if the maple outgrew its pot over the previous year.
But refrain from major pruning that stimulates excessive new growth right before dormancy again. Only do structural and maintenance pruning.
The Takeaway on Caring for Potted Japanese Maples Through Winter
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Check soil moisture and water carefully before and during dormancy to prevent roots from drying out.
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Insulate potted tree roots from cold and wind by surrounding pots with mulch or other coverings.
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Shield branches from sun and wind exposure which can burn bark and desiccate twigs.
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Fertilize lightly in spring to support new growth. Avoid late season fertilization.
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In fall, situate pots in protected areas and deeply water before ground freezes.
With some simple protective measures, your potted Japanese maples can survive tough winter conditions. A little TLC will keep them thriving year after year!
A customer from Durham asks:
“In October me and my wife bought two maples and one ginkgo from your farm. They’re still in their original pots, and I’d like to know if we can leave them outside until we plant them or if we should bring them inside.”
Its better to leave them outside where they receive natural water. They might get too hot in the garage and lose their leaves before they should, or they might dry out too much in the winter. It’s best to put the pots close together and in a place where they won’t blow over or where it will rain. Make sure the pots are not blocked by gutters or under and overhang or porch. The trees need rain to keep good moisture inside the pot, which happens naturally when theyre outside. Inside, its much more difficult.
From Zones 5 to 9, Japanese Maples do well in the ground. From Zones 6 to 9, they do well in pots left outside. That being said, if you know it will drop below 0°F, you might want to temporarily move them to the garage. Don’t cut it too close, and when the weather gets better, put the tree back outside. You can also put mulch around the pots so the roots are in Zones 5–9 instead of 6–9 when they’re off the ground.
Additional tags: Japanese Maples, Can I Leave Japanese Maples Outside Over the Winter in Pots, MrMaple.com, MrMaple Show
Winter care of your container grown Japanese maple tree
FAQ
How do you protect a potted Japanese maple in the winter?
Should I cover my Japanese maple in winter?
How to take care of a potted Japanese maple?
How cold is too cold for a Japanese maple?
How do you care for a Japanese maple tree in winter?
Proper insulation around the base of the tree is a key element in winter care for Japanese Maples. Apply a layer of organic mulch, such as straw or wood chips, to a depth of 2-3 inches. Mulching helps regulate soil temperature, preventing extreme fluctuations that can stress the tree’s roots.
Can You overwinter a potted Japanese maple tree?
If you have a potted Japanese maple, overwintering it outside can be challenging. One secret to protecting your potted tree is to insulate the pot by wrapping it in bubble wrap or burlap. This will help prevent roots from freezing and becoming damaged by the cold.
Do Japanese maple trees need winter protection?
Cold temperatures can cause serious damage to your tree. One of the keys to protecting your tree is providing adequate winter protection. There are several ways you can deal with winter damage and protect your Japanese maples. If you have a potted Japanese maple, overwintering it outside can be challenging.
Do Japanese maple trees grow in winter?
With some care and maintenance, your Japanese maples will thrive throughout all four seasons. Japanese maples may need protection in winter to prevent damage from cold temperatures, frozen soil, and winter winds. Young trees and trees grown in pots are more prone to winter damage than mature, established trees growing in the ground.
