Holm oak / Holly oak
(Quercus ilex)
Country of Origin : Mediterranean
Bonsai Styles : Informal upright, formal upright, Slanting
Zone : 7 – 10
Holm oak, also known as holly oak or evergreen oak, is a very long-lived evergreen tree that grows all around the Mediterranean.
This magnificent cousin of the cork oak tree has beautiful, deeply scored gray bark (small plaque-like squares). However, when young, the bark is smooth and grayish. The trunk of the tree, which gracefully gets corrugated with age, supports a rounded canopy. It is also easier to train as a bonsai than a common oak tree/English oak tree.
Please read common oak bonsai and cork oak bonsai for more details.
The evergreen leaves are simple in style, short-stalked, ovate-oblong, thick and leathery (coriaceous leaves) with a small hairy stalk. The alternate leaves are often toothed.
The upper surface of the leaves is smooth, glossy and dark green, and the underside of the leaves is downy and gray-green. The dark foliage contrasts vividly with silvery new growth.
In spite of the fact that the evergreen oak is an attractive tree, it isn’t as commonly cultivated as a bonsai. It is suitable to make a medium to large sized bonsai tree.
Read more about other bonsai trees species in : Types of bonsai tree
Best location to keep Holm oak bonsai tree
A holm oak bonsai should be kept in a bright, sunny location. It can be placed indoors and outdoors. When keeping the bonsai indoors, it should be positioned in a south or west facing window. However, if you have the choice, it would be best to place it outside during the summer. Keep it in partial shade.
When it is taken outside in spring, allow it to adjust gradually to the sun. Once it has become acclimatized, however, it can spend the whole day in direct sunlight.
In winter, keep it indoors, in a bright, unheated room near a window. Or you can protect it from cold in a hoop tunnel or cold greenhouse. It is a very hardy tree but its always wise to protect it from frost.
IMP: Refer to do bonsai trees need sunlight for more indoor and outdoor bonsai location ideas. Also, refer sunlight requirements for indoor plants for more indoor gardening ideas.
Propagation of Holm oak bonsai tree
Holm oak can be propagated from seeds. As soon as the seeds have matured in the fall, plant them in the seed bed. Before sowing the acorns, you can soak the acorns in water for 24 hours. Maintain a low temperature.
Watering Holm oak bonsai tree
Established holm oak is drought-tolerant. It can withstand occasional neglect in watering. Despite this, it is always a good idea to maintain a regular routine for watering your bonsai.
Do not overwater the holm oak bonsai. For this bonsai, when in doubt, watering less is better. It is possible to use ordinary tap water.
Keep soil a little drier over the winter but never dry out.
Read watering bonsai tree.
Wiring Holm oak bonsai tree
Almost all bonsai styles are feasible because of the tree’s natural habit. You can easily wire 1-2 year old branches of the tree. Perform the required pruning before wiring the tree.
Read : Detailed guide on How to wire a bonsai. This extensive guide includes all the wiring techniques and Do’s and Dont’s. It will also show you other bonsai training techniques which can be achieved without using wires.
Pruning Holm oak bonsai tree
When to prune Holm oak bonsai tree?
How to prune Holm oak bonsai tree?
Prune the branches in spring, before the new growth cycle, and shorten the new shoots from spring to autumn.
To encourage thicker branches in young plants, allow new shoots to grow to almost 8 inches before cutting them back. Cut back to 2-4 leaves. Remove all the crossing, downward, and double branches.
Read how to prune a bonsai to know about the right technique of pruning and more about defoliating a bonsai tree.
Repotting Holm oak bonsai tree
When to repot Holm oak bonsai tree?
Young trees can be repotted every 2-3 years in late spring. Older mature specimens can be repotted depending on how much the roots are pot bound. Do not prune more than 20% of the total root system.
Use a free-draining bonsai soil mix.
You can also make a bonsai soil mix by mixing loam, sand and peat moss (1:1:1). You can also compost, fired clay particles and sand in the ratio 1:2:1.
Please check out how to repot a bonsai to know everything about repotting and root pruning a bonsai.
Must Read: Bonsai Soil Recipes
Feeding Holm oak bonsai tree
During the growing season, feed your plants every two weeks with organic or inorganic fertilizers. During the winter, do not apply feed.
Read more about bonsai fertilizer and its application. This will also give you more details on how to feed flowering bonsai trees.
Diseases and pest of Holm oak bonsai tree
This bonsai is generally pest free.
Please make sure you read our comprehensive guide: How to identify and treat bonsai pests and diseases is a great resource for you to see all the organic and inorganic remedies you can use.
