Gardening with Gary

Gardening Advice from an Expert

Holly

Winterberry Plants:

Judy writes~ I have some winterberry plants, from the Holly family. I wanted to bring the stems in for the holidays, but I am concerned because one of my cats likes to eat flowers of all kinds. Do you know if these are poisonous like a typical holly plant?

A. To be on the safe side, I would not have them near any pets period, let alone ones who love eating flowers, leaves or fruit. Small tots can be harmed also and even adults if enough of the berry is consumed. Here is some information to back my case, plus a little history:

Canada Holly or winterberry is a familiar plant. At one time, tea brewed from its bark was considered a tonic, as well as treatment for fevers; externally, the bark was applied as a poultice to skin eruptions. It contains caffeine, which can be harmful to children or pets when ingested!

The berries were taken as a cathartic, and to expel intestinal worms. These folk remedies have been superseded by better, safer medicines.

There are pictures of the plant here:

http://museum.gov.ns.ca/poison/cdnholly.htm

http://www.ontariowildflower.com/pine_forest.htm

There are many species of Holly throughout the world both evergreen and deciduous. Two species commonly found in this area are Winterberry, Ilex verticillata and the American Holly, Ilex opaca.

Winterberry is a deciduous (losing its leaves in fall) Holly shrub with bright showy red berries that develop in autumn and remain attached to the tree through winter. There are male and female trees within the species that flower in the leaf axils; with only the female developing berries and only if there is male winterberry in the vicinity. Winterberry can be found in swamps, damp thickets and pond margins.

American Holly is an evergreen tree with a narrow, rounded, and dense crown of spiny leaves, small white flowers and bright red berries. The bark is light gray and the fruits also mature in autumn remaining attached through winter. Like Winterberry, there are male and female trees with only the female developing fruit. American Holly is commonly found in moist or well-drained soil like flood plains and in mixed hardwood forests. This tree most closely resembles the European variety, sp. aquifolium and is used during the holiday season in the same fashion.

Holly has long been viewed as an herb of protection. Boughs of Holly or wreaths were placed over doorways to grant peace, protection and prosperity to the homes it adorned. This practice, which was adopted by Christians, dates back to the Druids. The common name of “Christ's Thorne” was said to have come from the legend that Holly sprang up from the footsteps of Christ as he walked to His crucifixion, the thorny leaves representing His crown of thorns and the berries droplets of His blood. The leaves of Holly were used medicinally to treat a variety of disorders including fevers, pleurisy and worms. The fruit although considered poisonous to humans is a food source for a variety of birds and mammals.

Joyce writes~
Last spring, I asked about my holly bush which was taking over another evergreen and that we wanted to remove the evergreen. With your suggestions and directions, the evergreen is completely gone and the holly bush is growing and has berries on it. It now needs to be cut back a little. Can we do it now [June]? It seems to be growing a little lopsided which could be due to the evergreen or the getting rid of the evergreen.

A. That is great news about the holly. Sometimes shrubs get planted too close to each other and the bottom line is that one just has to go. Did you move the evergreen or just destroy it?

Here is some advice on pruning holly and when: Dead, diseased and broken wood can be removed at any time of year. The best time for general pruning is in late winter or early spring, immediately before growth resumes. Hollies may be pruned a second time in June before the new growth has matured. It may be necessary to give particularly fast-growing plants an additional light pruning or two during the growing season. Good judgment must be exercised when pruning flowering evergreens so as not to drastically reduce the amount of next season's flowering wood. Any pruning should be done as soon after flowering as possible. Severe pruning can usually be avoided if pruning is done annually.

It is important to have the necessary tools in proper working order for pruning your plants. These tools include a hand pruner, lopping shears, hedge shears and a curved pruning saw. Care should be taken not to cut too far back into the older wood, because new growth is not as readily produced from such wood.

When selectively pruning, it is a good practice to cut the growth back to a side shoot. Some species withstand relatively heavy pruning. Because shearing encourages the formation of additional lateral growth, a more dense habit of growth is created. The amount and manner of pruning depend to a large extent on the type of plant, its location and the particular tastes of the homeowner.

American holly may be pruned in December for Christmas greens. Chinese holly is also a source of attractive greens and may be trimmed in the early spring. When pruning American holly, always make the cut at a node, just above a lateral bud. Prune so as to maintain the natural shape of the tree. The shrubby Chinese and Japanese hollies can be more severely pruned and may require some additional light pruning during the growing season.

In late winter or early spring is the best time to prune your hollies. You can prune back the shrubs either 1/3 to 1/2 to rejuvenate the shrubs, but if you need to prune to keep the holly within bounds in the area, then you can prune them back to approximately 12 inches from the ground. This severe pruning should not be done on an annual basis, use the 1/3 to 1/2 which is the best for the shrubs. Please be aware that the pruning will expose the stems and make the shrub look unattractive until new growth has started. That is why early spring would be the best time frame as the shrub produces the most growth at this time.

Assistance from: Delaware Cooperative Extension www.bonsai-bci.com
www.backyardgardener.com