This section is from the book "The Gardener's Monthly And Horticulturist V18", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
In the summer of 1874, a large portion of the leaves on some of my grape vines (out-doors), were badly mildewed and dropped off. The mildew followed cold, damp nights. My vines are mostly trained on the southerly side of a tight board fence, with southeast and southwest exposures to the sun. Those with the southeast ex. posure, were very much the most affected by the mildew. Those parts of the vines on, or near the ground were not perceptibly affected - the heat of the ground (sandy loam), keeping warm the lower stratum of the atmosphere and counteracting the deleterious effects of the cold night air.
How near the ground, and why upon the ground, were the vines? The vines are planted midway between the posts of the fence (nine feet apart), cut back yearly close to the ground, and allowed to take their own course in growing (except pinching off the weaker shoots), until four years old, then narrow strips of boards are nailed horizontally from post to post, a foot from the ground, and laths are nailed vertically to the strips and the top rail of the fence, and the vines are tied to them. This brings the vine six inches from the fence, which leaves a space for the circulation of the air. I first tied the vines to vertical wires instead of laths, but found they slipped down under the weight of the leaves and fruit. The strongest shoot is selected, trained perpendicularly and cut off even with the top of the fence. Four arms on each side are trained horizontally and cut off at the posts - the arms being one foot apart, and the lower one a foot from the ground. Short fruit spurs (which should be renewed), are left at the joints of the arms.
If the shoot selected for the upright stock has not the requisite number of branches for arms, I train up shoots from the ground to supply the number wanted; and then cut off all the others, and also cut off, from time to time (oftener the better), the runners and superfluous shoots, unless I leave some vigorous ones to layer for new plants the next year. The new wood on the spurs is kept pinched back to about four leaves of the fruit - more fruit on the spur requiring more leaves. In handling the vines, care should be taken not to break off the buds of the arms; for a new bud (except at the end), seldom starts without more skillful treatment than is commonly applied. From vines, of varieties suitable to the climate, trained within the above-named limits, large, well-ripened fruit is generally obtained, if too many bunches are not allowed to grow.
Those arms of the vines (Concords as well as others) on which the leaves were badly mildewed and dropped off early in the season, were mostly winter-killed; while all the lower arms but one survived: The main stocks of two Concords were killed down to the lower arms; but none of the vines left on the ground were killed. The leaves on the lower arms, and on the vines lying on the ground, had not been injured by the mildew. A vigorous Eumelan, four years old (which lost nearly every leaf by mildew), received such a shock that what wood was not killed made scarcely any growth in 1875. Remedy - cut back to the ground and try a new growth. The partially killed Concords made a good growth - furnishing plenty of new wood to supply the place of that winter-killed.
My vines are mostly Concord, eight years old - the best variety yet for out-door cultivation in this region. Let no one who is limited to a few vines, be deluded into trying other highly praised or very promising varieties (often brought into market for a speculative purpose), but stick to the tried and reliable Concord for the present.
This experience of mine tends to show that vines trained on, or near, the ground, are not perceptibly affected by the mildew, and that vines badly mildewed are liable to be winter-killed. As the lower arms of the vines were protected by the snow, a part of the winter, it might be reasonably maintained that this prevented their being killed. But of the arms unprotected by snow, only those were winter-killed that had been badly mildewed; and a healthy Concord vine is believed to be hardy enough to withstand, unprotected, the coldest winter in this region. The winter-killing may have been the joint effect of mildew and the severity of the winter - the winter of 1874-5 being a very cold and trying one for vines and fruit trees.
[We have much pleasure in publishing this excellent practical communication. The point in regard to the comparative tenderness of wood in cases where the leaves fall early from mildew/ or any cause, accords with numerous observations recorded in our columns in regard to raspberries and blackberries, and even the grape; and then as regards protection, it is- also known that though a raspberry cane that prematurely loses its leaves is killed by severe frost - it yet is perfectly safe when covered with earth. It is safe, therefore, to say with "Mystic," that it is both mildew and frost that destroys the grape wood. It is worthy of further remark that all methods of culture seem to have their peculiar diseases. It has been noted that grape shoots trained or growing near the ground, are less liable to mildew than when growing higher up - but on the other hand the fruit maturing in these lower vines are more liable to the disease known as the grape rot. This has been often observed, and it came again particularly under our notice at Mr. Bassett's vineyard, at Hammonton, last year, - Ed. G. M.]