This section is from the book "The Gardener's Monthly And Horticulturist V24", by Thomas Meehan. See also: Four-Season Harvest: Organic Vegetables from Your Home Garden All Year Long.
A correspondent recently inquired about this variety. An English grape grower, writing to the Gardeners' Magazine, names it at the bottom of his list; but has the following good points to note concerning it:
"The only other black variety I shall recommend is Gros Colmar, unquestionably the most telling of all the black kinds. Its clusters of huge deeply-colored berries are sure to bring the cultivator much credit, and when fully matured it is not by any means indifferent in quality. Complaints are frequently made of the inferiority of Gros Colmar. but it has not deserved all the hard things that have been said of it, and in many instances the grower rather than the grape has been at fault. When we hear it spoken of as being so poor in flavor as to be hardly worth eating, we may be sure that it has either been grown in too low a temperature or has been cut before becoming perfectly ripe. Gros Colmar is not a cool-house grape; it requires a temperature fully equal to that necessary for the Muscat of Alexandria. I was perfectly aware of this when in charge of the Ealing Park Gardens, and in planting my long lean-to Muscat house a few canes of the Gros Colmar had a place in it. They are now removed to enable me to devote the house entirely to Muscats ; but during the two or three years the latter were invariably of a rich golden hue two or three weeks before Gros Colmar had taken on the deep color for which it is distinguished.
It has also been long known to me that the bunches are not fit to cut immediately the berries are black ; and further, to have the grape in its highest perfection, it should hang from six weeks to two months after the coloring process has been completed. It is remarkable, considering the length of time it will hang, for the extreme thinness of its skin, which to many is a decided recommendation".