This section is from the book "The Gardener's Monthly And Horticulturist V22", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
In a late number of the Gardener's Monthly, pp. 354,1 notice C. E. P's queries as to the hardiness of Ligustrums Ibota and coriaceum, and the best methods of protecting them. The Ligustrums in question, possess about the same degree of hardiness as the Ligustrum Japonicum, of which indeed coriaceum may be termed a variety. During moderate winters, a light covering of evergreen boughs, or a sheaf of straw bound together at one end, placed loosely over the plant and tied to a stake will generally suffice to save these Privets. The simple object must be to repel the injurious effects of cold winds, sleet and sun, during the hard freezing and frequent thaws of early spring. For the same purpose, a light mulching of hay or straw at the foot of the plant is beneficial. All such methods as binding up tightly with straw, covering with barrels, etc., are dangerous. The plant may thus die for want of a circulation or air during extreme cold. There is a wide-spread ignorance of the best methods of protection for half hardy plants, and, in consequence, even our half hardy plants do not succeed as they might under wiser treatment I understand the term half hardy as indicating a capacity to live out of doors during some winters with due protection.
In spots like parts of Greenwood Cemetery, Brooklyn, N. Y., it is surprising to observe sometimes the tender plants that will survive uninjured the severest winters. No artificial devices can protect plants as thoroughly as such sheltered spots.
Sometimes I wish there was no such term in vogue as "half hardy."" People led away by the expression, are all the time trying to partially expose certain plants only to lose them. Even so-called experts will persist in planting out these Ligustrums, Aucubas and the like as far south as Baltimore and Washington, with little better success than we have about Philadelphia and New York. As I have already remarked, it is the severe changes of late winter and early spring that kill them and not biting cold. Horticulture would be positively benefitted, if people would never attempt to leave these half hardy plants out. As it is, many become more or less discouraged with all planting. Failure must in time, dampen their enthusiasm.
Let me refer your readers to the description of a temporary structure for a cheap protection of half hardy plants by S. B. Parsons in the Gardener's Monthly. Only by this method, or by the use of pits and cellars for protection can half hardy plants be satisfactorily enjoyed.
Acacia lophantha, we have found less hardy than the above named Ligustrums, which are indeed among the most enduring plants usually classed as half hardy. Frequently, Acacia lophantha stands the winter tolerably, if protected by masses of evergreen trees. For hardiness, however, it as well as A. julibrissin, is greatly inferior to the beautiful Japan Acacia Nemu, which has stood for some years perfectly well in Central Park, New York.