This is a group of hybridized hollies. They were developed by “crossing” other holly types to produce cold-hardy plants with beautiful foliage – 2 noble goals.
The term blue holly represents several hollies within the Meserve Holly group. I do have my favorites, but each one has its own beauty especially when sited correctly. By sited correctly I mean planted in favorable conditions for that particular plant.
The blue holly group is certainly cold hardy. In fact, as far north as into parts of zone 4. Certain varieties have been found to be a bit more cold-hardy than others. For example, Blue Maid Holly (pictured above) is considered one of the hardiest.
Note: Even though blue holly is cold hardy, I would still spray them with an anti-transpirant as an added measure of winter protection. Any broadleaf evergreen will suffer winter burn if conditions are right, such as frozen ground, winter sun and wind.
Form and Growth Habit
Blue holly’s mature form is either pyramidal or upright and rounded. When healthy (this goes back to “siting correctly”) it is a dense evergreen. The leaves are glossy and almost blue-green. There are fine, spiny teeth on the leaf edges – but not as pronounced as those on American Holly.
Blue holly varieties are dioecious, meaning there are male and female plants. If you want the female to produce berries you’ll need a male holly nearby (at least within 300 ft.).
Generally, they like full sun. They will get thinner with less light, which in a “natural” setting can be acceptable.
Blue holly adapts to different soil types, but avoid planting in poorly drained soil. Plants that are in heavy wet clay can, for example, weaken and become predisposed to disease like Phytophthora.
How Do They “Work” In The Landscape?
When I say this plant is versatile in planting design, I’m not kidding.
The top picture shows blue holly as a hedge. Is that beautiful or what? Notice the space this hedge has to grow forward – very smart. You could plant a groundcover or low perennial in that open space while the holly continues to grow.
The picture to the right shows a blue holly used as a single plant in a mixed garden. It offers year round interest with its deep, rich color and texture.
I have also used blue holly as a screen plant to hide utilites. In the border garden it masses nicely in groups of any number (they say always work in “odd” numbers). There you can arrange them in a stagger and let them grow together naturally. For foundation plantings it makes an excellent corner plant either by itself or in a grouping.
As always (I’ll bet you know what I’m going to say) space blue holly appropriately. They have the potential to get 8 – 10′ high and 6 – 8′ wide.
Here are some of the blue holly varieties you’ll probably come across:
- ‘Blue Angel’
- ‘Blue Boy’
- ‘Blue Girl’
- ‘Blue Maid’
- ‘Blue Prince’
- ‘Blue Princess’
- ‘Blue Stallion’