Posted by Brent Wilson on 10/29/2016 to Fertilizing & Watering Tips
When planted right and in the environment, Cryptomeria trees, commonly called Japanese cedars, are very easy to grow. While Cryptomeria trees are most often seen planted in straight or curved staggered rows for screen plantings, they also makes a nice specimen tree in larger landscapes or a corner plant to frame in tall homes and other structures. Their look makes them a natural fit for Asian-themed and conifer gardens. They can be grown in large containers however will eventually need to be transplanted to the landscape.
Here's a breakdown of what you need to know to plant and care for Cryptomeria trees...
Cryptomeria will grow in most any average, well-drained garden soil. They prefer a fertile, acidic, consistently moist but well-drained soil. As with so many other ornamental plants, constantly soggy soils will cause root rot.
Testing Soil Drainage
If you are uncertain about soil drainage in the area you intend to plant your Cryptomeria, it's well worth taking the time to test it before planting.
To test soil drainage, dig a hole 12" wide by 12" deep. Fill the hole with water and let it drain. Then, after it drains, fill it with water again, but this time clock how long it takes to drain. In well-drained soil the water level will go down at a rate of about 1 inch an hour. A faster rate, such as in loose, sandy soil, may signal potentially dry site conditions and a need to add some moisture retentive organic matter. A slower rate indicates poor draining soil and is a caution you need to improve drainage, plant in a raised mound or bed, or look for plants that are more tolerant of wet or boggy conditions.
Cryptomeria grow well in an acid to neutral soil ranging from pH from 5.0 to 7.0 on the pH scale. Most average garden soils fall between a pH range of 6.0 to 7.0.
Testing Soil pH
Soil pH is a measurement of the alkalinity or acidity of soil and is measured on a scale of 1-14, with 7 as the neutral mark. Any measurement below 7 indicates acid soil conditions, and anything above 7 indicates alkaline.
If you're unsure about the pH of your soil and whether or not it's suitable for growing Cryptomeria it's a good idea to test the soil pH in the planting area. You can quickly test soil pH with an inexpensive soil pH tester probe. To raise the pH (make more alkaline) you can add pelletized limestone to the soil. To lower the pH (make more acid) you can apply Soil Sulfur, Aluminum Sulfate, or Chelated Iron. Adding organic compost to the soil or using compost as mulch can also help to increase acidity and maintain acid soil conditions.
Learn More: What is Soil pH and How To Adjust It?
Cryptomeria like life on the sunny side, though will also tolerate some shade or filtered sun. For best overall performance, 6 hours direct sunlight per day is suggested.
How To Plant A Cryptomeria Tree
Scroll down for container planting instructions and care tips
Start by digging your planting hole at least two to three times as wide and as deep or not much deeper than the root ball of your plant. The wider the hole the better. Place native soil removed from planting hole around the perimeter of the hole, in a wheel barrow, or on a tarp.
Depending on the type, fertility and porosity of the soil in the planting area, it might be beneficial to mix in some compost or a soil amendment to the native soil removed from the planting hole. When planting in heavy clay or other compacted soils it is beneficial to thoroughly mix in a good soil conditioner, planting mix, sand or other organic matter at a 50/50 ratio with the soil removed from the planting hole to enhance porosity and ensure good drainage. When planting in very sand or quick-draining soil, it's beneficial to mix in some top soil, organic compost, or peat moss to the native soil to help retain moisture. When planting in fertile, loamy, moist but well-drained soil there may not be a need to amend soil.
To remove your Cryptomeria tree from the container it was growing in, firmly grasp the base of the tree and try to gently lift and remove it from the container. If the root ball is stuck in the container place the plant on it's side and gently tap or push down on the side of the container to loosen the root ball. If that doesn't work, use snips to cut the container away. After having removed the plant from the container, carefully loosen some feeder roots around the surface of the root ball. If your plant is root bound, you can spray the sides and bottom of the root ball with a stream of water from a garden hose. This will help to wash away some soil from the exterior of the root ball making it easier to loosen roots.
Place your Cryptomeria in the planting hole so thatthe top edge of the root ball is at or slightly above ground level. It may be necessary to place some of your soil mixture in the bottom of the hole to achieve the proper planting height.
Note: If the soil is poorly drained (constantly soggy or wet) improve drainage in the area or select a different plant species more tolerant of wet soils.
After setting your Cryptomeria in the planting hole, use one hand to hold the plant straight and your other hand to begin back-filling your soil mixture around the root ball, tamping as you go to remove air pockets. When you have filled the hole to the halfway point you can soak the soil. Then continue back-filling to the top edge of the root ball. To avoid suffocating your plant, avoid placing any soil on top of the root ball.
Step 6 (Optional)
If the the planting site is far from a water source, you can use remaining soil mixture to build a water retaining berm (catch basin / doughnut) around the outside perimeter of the planting hole. This berm will help to reduce watering frequency by collecting water from rainfall and irrigation. The berm can be removed after a growing season or two when the plant has established itself.
Next, deeply water the planting area, including the root ball, to a depth equal to the height of the root ball. For an extra boost, to stimulate early root formation and stronger root development, you can water your newly planted Cryptomeria with a solution of Root Stimulator, which reduces transplant shock and promotes greener, more vigorous plants.
Apply a 1 to 2" layer of cured, shredded or chipped wood mulch or bark, or a 3- 4" layer of pine straw, around your newly planted Cryptomeria. Avoid the use of freshly chipped or shredded wood for mulch until it has cured in a pile for at least 6 months, a year is better. Avoid placing or piling mulch directly against the base of the shrub as this could cause the bark to rot.
Planting A Cryptomeria in a Container
Cryptomeria growing in pots appreciate a moist but well-drained soil. Constantly soggy or wet soil can and often will cause root rot and other harmful plant diseases. Therefore, I suggest using a quality potting soil or potting mix, or a 50/50 combination thereof, and a container with a drainage hole(s). You can add 10 percent pumice or perlite to the soil mix to enhance drainage.
Choose a container that is large enough to allow for 2 to 3 years of growth before shifting up to a larger size container or transplanting to the landscape. This might mean your planting pot would be 8 inches or more in diameter (width) than the root ball of your plant.
Container color will matter as well. Not only will you want to pick a color of container that goes well with the foliage color and texture of your Cryptomeria, you'll also want to pick a container that matches the style of your home or other structures and other plants in the surrounding environment.
Many nursery & garden centers offer a wide variety of containers to choose from. Before heading out to buy a container take pictures of your home and the surrounding environment. Doing so will help you to choose just the right color and style.
How To Plant Cryptomeria In Containers
Before filling your container with the soil mix, I recommend lining the bottom with shade cloth or a porous landscape fabric. This will keep the drain holes from becoming stopped up with soil. If you place gravel, stones or other materials in the bottom of the container lay the fabric over it.
To remove your Cryptomeria tree from the container it was growing in, firmly grasp the base of the tree and try to gently lift and remove it from the container. If the root ball is stuck in the container place the plant on it's side and gently tap or push down on the side of the container to loosen the root ball. If that doesn't work, use snips to cut the container away. After having removed the plant from the container, carefully loosen some feeder roots around the surface of the root ball.
Pour a small amount of your soil mixture in the bottom of the container. Set your plant in the container and make necessary adjustments by adding or removing some soil so that the top edge of the root ball will sit 1 inch or so below the rim of the container.
Backfill with your potting soil around root ball, tamping as you go, until the level of potting soil is even with the top edge of root ball.
Water thoroughly until water starts to drain from the holes in the bottom of the container. Add more potting mix if settling occurs during watering.
Step 6 (Optional)
Apply a 1/2" layer of wood chips to soil surface to help conserve moisture.
How To Care For Cryptomeria
Feeding - Watering - Pruning
How To Fertilize A Cryptomeria Tree
Cryptomeria are moderate feeders that will benefit from fertilization.
When to fertilize a Cryptomeria tree?
I fertilize my Cryptomeria trees in late winter or very early spring, before new growth begins to emerge. If trees look like they could use another feeding I do so again in late spring or early summer. Cease fertilization of Cryptomeria two months prior to the average first-frost state in your area.
What type of fertilizer?
When feeding Cryptomeria, I use a slow-release shrub and tree fertilizer at rates recommended on the product label. Alternatively, you can feed with a mild, organic plant food.
To conserve moisture throughout the growing season and suppress weed growth, I also always apply a 1 to 2" layer of cured, shredded or chipped wood mulch or pine straw around the tree in late winter. As the mulch decomposes it will add vital nutrients to the soil that your tree will appreciate.
Note: Avoid the use of freshly chipped wood for mulch until it has cured in a pile for at least 6 months, a year is better. Avoid placing or piling mulch directly against the base of your treeas this could cause the bark to rot.
How much fertilizer?
This will depend of course on the size of the tree you are fertilizing and the type of fertilizer. Regarding slow-release shrub and tree fertilizers, you'll find application instructions on the package label.
Where to spread the fertilizer?
The majority of the feeder roots responsible for absorbing nutrients are in the top 12 to 18 inches of soil. Spreading fertilizer on the soil surface is sufficient to reach these feeder roots.
Spread fertilizer evenly around each tree, beginning a couple feet from its trunk, and then one foot beyond the drip line (branch perimeter) for every 5 feet in tree height.
Note: If the soil is compacted or subject to excessive water runoff, the fertilizer can be applied in a series of holes 6 to 8 inches deep in the same area with about five holes per 1 inch of trunk diameter.
Cryptomeria will thrive in an acid to neutral soil with a pH of 5.0 to 7.0 to on the pH scale. Most average garden soils fall between a pH range of 6.0 to 7.0.
Learn More: What is Soil pH and How To Adjust It?
How To Water A Cryptomeria Tree
When estbalished, Cryptomeria will be quite drought tolerant, However, when young trees will will require regular watering in absence of rainfall in order to thrive. Cryptomeria do not like constantly constantly soggy or wet soil, which can lead to root rot and other harmful plant diseases. So be careful to avoid over-watering them!
At Planting Time
Immediately after planting deep soak the soil in the planting area, including the root ball, to a depth equal to the height of the root ball. For an extra boost, to stimulate early root formation and stronger root development, you can water your newly planted Cryptomeria with a solution of Root Stimulator, which reduces transplant shock and promotes greener, more vigorous plants.
During the First Active Growth Season
In average garden soil, and with sufficient rainfall, you should not have to water your newly planted Cryptomeria every day. More often than not, this causes soggy soil conditions that can lead to root rot and other plant diseases. In the absence of sufficient rainfall, water only as needed to keep the rootball and surrounding soil damp to moist.
Keep in mind that deep soaking less frequently is much better than splashing just a little water on the plants every day. Trees planted during the winter dormant season, when plants are not actively growing and evaporation is much slower, will require much less water. So, be extra careful not to overwater during winter!
When established, Cryptomeria will require supplemental irrigation only during prolonged periods of drought. If during a dry spell you see foliage wilting and/or fading in color this could be a sign your plant needs water.
How To Prune A Cryptomeria Tree
Cryptomeria do not require pruning. That said, damaged stems should be removed as they occur. A stray stem that is spoiling the shape of the tree can be snipped off any time of year.
Plant Long & Prosper!
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