How to Grow and Care for Scarlet Oak Tree

Scarlet Oak Care

Here are the main care requirements for growing a scarlet oak tree.

• Plant in full sun.
• Choose a permanent home when planting scarlet oak because it grows a deep taproot and is a very poor candidate for transplanting.
• Dig a wide hole, not a deep one. Dig a hole twice as wide as your scarlet oak tree’s roots are deep.
• Mulch with organic mulch 2 to 3 inches high, but do not let it touch the trunk.
• Fertilization and excess watering are not necessary for scarlet oak trees.

Light

Provide your scarlet oak with plenty of sun for it to thrive and offer the best fall color.

Soil

Plant your tree in dry, well-drained soil that is preferably acidic.

Water

Medium water is all that is required to keep the scarlet oak happy. It is drought-tolerant once established.

Temperature and Humidity

A scarlet oak grows best in zones 4 through 9. It does not do well in extreme dry heat.

Fertilizer

Resist the urge to fertilize your scarlet oak; it is not necessary.

Pruning

Never prune an oak tree in the summer months. It’s best to prune an oak tree when it is dormant so you can avoid the onset of oak wilt disease. To prune an oak so that it can have more air circulation, use disinfected pruners to remove dead, diseased, weak, or damaged branches that feel brittle, have wounds, or are discolored. Also remove crossed limbs and shoots that are growing straight up or down. Prune up to 13 of old wood each season.

Propagating Scarlet Oak Tree

Though it’s slow, the most common way to propagate an oak tree is by using an acorn, which is essentially the tree’s seed encased in a very tough shell. Acorns don’t typically turn into oak trees because once they fall from the tree, they are scooped up by wildlife or they lay under the tree without enough sun or nutrients to help them grow. Here’s what to do after you’ve gathered a batch of acorns late in the season:

1. Take the caps off of the acorns.
2. See which acorns are viable by putting them in a bowl of water for five minutes. Discard floating acorns (they are not viable).
3. Now you can stratify your acorns, which means you are simulating a cold condition to trick the acorns (seeds) into germination. Dry off the saved acorns, and put them in a plastic baggie filled with damp vermiculite, perlite, peat, or sawdust. Seal the bag.
4. Put the bag in the refrigerator for 45 to 60 days. During that time, look for germination of the acorns to begin.
5. Put the germinated acorn in a small pot with good potting soil and keep moist.
6. Keep the pot in a spot that is warm enough, but not too hot, with direct sunlight in the morning and shade in the afternoon.
7. When the seedling is about a foot or so high, it can be transplanted into a permanent full sun spot in your yard.

Common Pests & Plant Diseases

Oaks are susceptible to several pests, including leafeaters, cankerworm, forest tent caterpillars, gypsy moths, borers, and a host of other pests.

Oak wilt, a fungus disease, can cause problems with scarlet oak trees. Trees infected with oak wilt cannot be saved. Cankers can also form on scarlet oak trees. Fungal diseases can also cause heart rot.

Common Problems With Scarlet Oak Tree

Oak trees are usually unaffected by problems, except when it comes to growing in the wrong type of soil (alkaline) and suffering from the ubiquitous disease, oak wilt. Here’s what to look for:

Yellowing Leaves

Chlorosis of leaves is a sign the tree is not doing well because of alkaline soil. It’s best to amend the soil, specifically treating it with sulfur to make the soil more acidic.

Browning Leaves

Leaves that are brown at the outer edges but still somewhat green in the middle may mean the tree is suffering from a fungal disease known as oak wilt. During the spring and summer, the leaves usually wilt and fall off as a result of oak wilt. Sap beetles are known to spread this disease through the tree’s wounds. It’s impossible to save a tree infected with the disease. Prevention is best, which is why it is not advisable to prune trees between April and August when sap beetles can enter fresh wounds.