Barberry bush used as a hedge row.

Introduction

Barberries, from the genus Berberis, are commonly used in gardens as foundation bushes due to their low maintenance requirements and adaptability. They can also be used as hedge pants due to their uniform growing pattern. There are over 400 species of Barberry, including B. thunbergii, B. julianae, and B. x mentorensis (Patterson, “Gardening Know How”). This article will be focusing on the Mentor barberry (B. x mentorensis).

The Mentor barberry is a deciduous shrub from the family Berberidaceae. People living in zones 5 to 8 can enjoy its pale yellow blooms in April and May. They grow to between five and seven feet tall when exposed to full sun or part shade. The Mentor barberry is a semi-evergreen with sharp-thorned stems. It is a hybrid plant whose parents are B. julianae and B. thunbergii. They have ellipic-ovate dark green leaves that are 1-2 inches long and pale underneath. Foliage develops a yellow-orange-red color in the colder areas of its growing range. Fruit may be sparse or absent on this hybrid plant, but is dull red in color when it does appear. Their water requirements are from dry to medium amounts of water. They can adapt well to a wide range of soil types, as long as they drain well (Patterson, “Gardening Know How”). They are low maintenance bushes that can tolerate deer, drought, erosion, heat, urban pollutants, and dry soil. They offer susceptibility to verticillium wilt, rust, root rot, anthracnose, and mosaic virus.

Verticillium wilt is caused by the soil-borne fungi Verticillium albo-atrum and Verticillium dahliae. Verticillium dahliae is the most common species that attacks woody ornamentals in the United States. This fungus exists in the soil indefinitely and, many times, the host doesn’t exhibit any sign of infection. Rust is a fungal disease that can cause leaf spots or the leaf to turn the entire leaf yellow or brown. It can also cause premature leaf drop, curling, and withering of foliage. Fungicides may be used to fight this during a plant’s dormant period. Root rot is one of the greatest causes of crop loss. It can kill plants, slow or stop plant growth, and suppress plant quality. No one fungicide can prevent root rot, so the fungi must be identified before you can try to eliminate it. Anthracnose is a general term used to describe diseases that result in a wide range of symptoms including leaf spots, blotches or distortion, defoliation, shoot blight, and twig cankers. It does not cause permanent damage to established trees however, continuous defoliation can cause a decrease in the tree’s vigor, weakening the tree, and making it susceptible to opportunistic pests (“Plant Diseases”). Mosaic virus can sometimes be difficult to detect. It’s symptoms include yellow stripes or spots on foliage, wrinkled or curled leaves, stunted growth and reduced yields, and fruits develop raised “warty” areas on them. This virus overwinters on perennial weeds and is spread by the insects that feed on them. Aphids, leafhoppers, whiteflies, and cucumber beetles are among these insects. Cuttings from infested plants will also carry the virus. There is no cure for a virus infected plant, so it’s important to prevent the disease from ever entering your garden or field.

Propagation Methods

There are many ways to propagate the Mentor barberry. One way to propagate them is through seeds. They can be fall-sowing or spring-sowing that have been stratified two to six weeks at 40 degrees Fahrenheit. Some species may require stratification for up to two to three months. It’s extremely important to remove all pulp from the seeds. Seedlings are susceptible to damping-off and some even to black stem rust.  The Mentor barberry is primarily propagated through rooted stem cuttings. Cuttings taken from spring to fall can be rooted under mist (Loucks, “Garden Guides”). Hormones, including IBA, aid in the rooting process to help the roots develop faster. You should always use a cutting that is green-yellow in color, never brown. Timing, application of mist, and the hardening-off process are critical. Although rooting can be more expensive, it saves more time as compared to growing every bush from a seed. Greenhouse grafting of some selected types is also practiced and layering is occasionally done. Division of crowns is useful for small quantities of plants. Provided below are step-by-step instructions on how to perform a cutting propagation.

Step-by-Step Cutting Propagation

Step 1: Disinfect pruning tools using a nine parts water, one part bleach solution. This prevents the spread of disease onto the barberry plant.

Step 2: Take a 4- to 6-inch cutting from the barberry push using the disinfected pruning tools. Make sure that the cutting is current year plant stem growth that is beginning to mature and turn firm.

Step 3: Remove the lower one-third of any stem leaves or buds that may be growing on the cutting. This will decrease water loss and focus the stem’s energy on root growth.

Step 4: Dip the end of the stem in a small amount of rooting hormone. Gently tap the end of the stem to remove excess hormone. Do not pour the rooting hormone back into the container because this could introduce disease to the container of hormone.

Step 5: Fill a rooting tray with a sterile rooting medium that has been moistened with water. Stick the cut end of the stem into the medium to a depth of half of the length of the cutting. Space the cuttings so the leaves of each stem are not touching.

Step 6: Water the cuttings and the medium and cover the container with a clear plastic cover or place the tray in a clear plastic bag to cover it. Mist the cuttings regularly during the rooting period to keep the soil moist and the humidity high. Monitor the moisture level to prevent the environment from becoming wet because this can cause stem rot.

Step 7: Pull on the stem cuttings starting four to six weeks after sticking to see if there is resistance from root growth, Transplant cuttings to individual containers filled with sterile potting soil once the roots reach a length of one inch. Continue to grow the cuttings in a protected environment for the first year (Loucks, “Garden Guides”).

Yellow blooms of the Mentor barberry.

Conclusion

As you can see, the Mentor barberry is a hardy, deciduous shrub that is relatively easy to propagate and is very common among gardeners. This late spring and early summer shrub is durable and easily adaptable to many conditions. They are hardy, however they are susceptible to a few plant diseases. All-in-all, they are a good pick for someone who wants a low maintenance plant for their enjoyment.

Works Cited

Hartmann, Hudson T., Dale E. Kester, Fred T. Davies, and Rovert L. Geneve. Hartmann & Kester’s Plant Propagation: Principles and Practices. 8th ed. Boston: Prentice Hall, 2011. 781-782. Print.