Inkberry Holly (Ilex Glabra) Grow & Care Guide

Written by Iris

Nov 13 2021

Inkberry Holly (Ilex Glabra) Grow & Care Guide
Inkberry Holly (Ilex glabra) is a native compact shrub in the Aquifoliaceae that maintains leaves all year round. Inkberry Holly is a relatively slow-growing species that can grow up to 5-8 feet tall. Ilex Glabra sometimes forms clusters with many buds, making it an excellent plant for low hedges or borders. Inkberry Holly leaves are evergreen and toothed, reaching up to 2.5 inches. They are dark green and shiny on top and lighter and darker on the bottom.

Inkberry Holly Quick Info

Botanical/Scientific Name Ilex glabra
Common Name Inkberry holly, gallberry shrubs
Plant Type Evergreen shrub
Light Requirements Full sun to part shade
Soil Requirements Moist well-drained soil
Bloom Time Spring, Early Summer
Flower Color Greenish white
Fruit Time Early fall
Fruits Pea-sized black fruits

How to Grow Inkberry Holly (Ilex Glabra)

Inkberry Holly Propagation with Seeds

Each Inkberry Holly contains about four seeds. Growing inkberry holly from seed can be difficult as the seed germination is slow, requiring anywhere from sixteen months to three years. In addition, it can take another three years before the Inkberry Holly shrubs produce any flowers. A specialized coating to survive harsh winters protects holly seeds; however, this pulp-like substance also makes propagation more difficult. Nonetheless, growing Inkberry Holly shrubs from seed propagation can be done, with patience. Collect Inkberry Holly berries and break the skin off. Rinse the seeds in cold water and then plant them in soilless potting medium within a large flat. Cover the flats and place outdoors in a protected area over the winter. If all goes well, the Inkberry Holly seeds should germinate by spring. Otherwise, they'll have to remain through another winter.
Read More:
12 Wonderful Evergreen Shrubs for Your Garden

Inkberry Holly Propagation with Wood Cuttings

Now, there are two types of Inkberry Holly cuttings that you can use for propagation. The most popular cuttings are those taken from hardwood growth during cold weather or their dormant period.  However, you can also use softwood cuttings taken in summer or late autumn.
For hardwood cuttings, you should cut above and below the bud unions from the branches for best growth. If you want to use softwoods, cut about 0.24 inches (0.6 cm) below a leaf node.
Once this process is complete, dip the cut ends into rooting hormone then plant your cuttings in a mixture of potting soil and sand. Inkberry holly cuttings need a well-lit location and regular watering to develop a healthy root system. Once established, you can transplant each baby plant in its permanent spot.
Ilex glabra

How to Care for Inkberry Holly (Ilex Glabra)

Inkberry Holly Light Requirements

Inkberry Holly shrub prefers full sun, especially in cooler climates. It can, however, tolerate partial sun and may appreciate some shade in warmer areas.

Inkberry Holly Soil Care

Inkberry Holly is best planted in average, medium to wet soils and in full sun to part shade. It is adaptable to both light and heavy soils but does best in rich, consistently moist, acidic soils. It does not do well in alkaline soils. In native locations, it prefers sandy, acidic woodland soils and is often found along the edges of swamps and bogs.

Inkberry Holly Watering

Inkberry Holly shrubs should be watered 1-2 times per week, depending on the weather. Trees do not require more watering, except in drought conditions where there is less than 1 inch of rain per week. Groundcover, however, should be watered 3 times per week for 3 months.

Inkberry Holly Temperature & Humidity Care

Inkberry holly thrives in a wet, cool climate. This distinguishes it from other hollies, which often prefer drier locations.

Inkberry Holly Fertilizer

Fertilize all your shrubs, evergreens, trees, groundcover, and perennials once every 3 weeks. This should be done during the months of April, May, June, July, and August.

Pruning Inkberry Holly

Holly Inkberry is a shrub that should be pruned in the late spring to maintain the shape and height of the plant.
In general gardening terms, pruning is probably the most misunderstood gardening chore, and certainly, the chore that is most likely neglected. When we specifically look at pruning Inkberry holly, this misunderstanding and negligence can be magnified.
Pruning has been described as a “combination of art and science.” I personally find pruning to be one of the most relaxing yet rewarding chores in the garden. Pruning a specific plant to look a specific way, involves art in creating a unique definition for a specific plant, and it involves science in understanding the physical growing habits of the plant to be pruned.
Ilex glabra

Ilex Glabra Pests & Diseases Care

  • Leaf Spot
The leaf spot disease that affects Inkberry Holly is called anthracnose. Anthracnose appears as light tan to darker brown circular or irregular spots on the leaves. It spreads through spores in moist weather, which you can see with your naked eye as pinprick-sized pink dots in the leaf spots. To control, prune out diseased limbs and/or apply a fungicide containing thiophanate-methy or chlorothalonil until the disease is gone. To prevent anthracnose, avoid overhead watering.
  • Root Rots
Root rots can also affect the inkberry holly, especially Phytophthora and Thielaviopsis black root rot. They both cause yellowing of the leaves, early leaf drop, slow growth and, eventually, branch dieback, and occur most often with flooding and extreme heat. Fungicides cannot cure the holly plant of this disease but can stop the spread. Thiophanate-methyl will help with Thielaviopsis root rot and etridiazole and metalaxyl with Phytophthora. As the diseases cannot be cured, prevention by planting the Inkberry Holly in well-draining soil is your best bet.
  • Cankers
Botryosphaeria canker affects weaker Inkberry Holly plants, usually following extremely high or low temperatures and drought. The canker causes similar symptoms to root rot, including yellowing of the leaves and dieback. The cankers appear as sunken or cracked patches of wood, and girdle the stems so nutrients cannot reach the leaves. Prune out diseased branches as you notice them and take better care of the holly, watering during drought and mulching to retain soil moisture.
  • Pests
Most pests don't bother Inkberry Holly but some do. Aphids attack new growth and scale insects are sometimes a problem, but both can either be removed by hand or with a quick blast of water. The iInkberry Holly leaf miner can be a larger problem, creating ragged leaves. In small infestations, you can pick the leaves off the plant, while larger infestations may require pesticides. During droughts, spider mites can also appear.
Ilex glabra

Ilex Glabra Varieties

Densa grows to 3 to 4 feet in height with a slightly greater width.
Compacta grows to 3 to 4 feet in height with a spread up to 6 feet. It has a tighter, more rounded growth habit than other forms.
Shamrock grows to 4 feet in height and spread. It has bright green foliage and is known to sucker less than other varieties.
Ilex glabra

Inkberry Holly Care FAQ

How tall does Inkberry Holly get?

In the wild, inkberry holly is often found in bogs, but it grows just fine in typical garden soil. It's a broad spreading, semi-stoloniferous shrub 6 to 8 feet tall and 8 to 10 feet wide.

Is Ilex Glabra toxic?

Warning: All Ilex species may be somewhat toxic if ingested. Sensitivity to a toxin varies with a person's age, weight, physical condition, and individual susceptibility. Children are most vulnerable because of their curiosity and small size.

Is inkberry holly edible?

While the berries aren't edible for humans, many birds and small animals are fond of them in the winter. Growing inkberry holly in your yard is a simple project, as these plants are almost carefree.