This section is from the book "The Gardener V2", by William Thomson. Also available from Amazon: The New Organic Grower: A Master's Manual of Tools and Techniques for the Home and Market Gardener.
WE commend Mr Henderson's forcible and seasonable remarks on the ripening of late Grapes in our present issue to the particular attention of those of our readers who are in-terested in the matter. It is a singular fact - and perhaps one not sufficiently recognised and taken into consideration - that our very highest flavoured Grapes are, with scarcely an exception, to be found among those to which long practice has assigned a higher temperature than is considered necessary for the general run of Grapes, - such, for instance, as the Muscat of Alexandria and its varieties, the Frontignacs, etc, which are beyond question in the front rank of highly-flavoured Grapes when ripened under the influence of a high temperature, abundance of light, and a dry atmosphere. But grown and ripened under circumstances the reverse of these - i.e., started late in the season and ripened late in a comparatively low temperature and damp atmosphere, these very Grapes never take on that finish which is a sure sign and accompaniment of high flavour and long-keeping qualities. Badly-ripened Muscats, as pointed out by Mr Henderson, are amongst the most distasteful of Grapes, and never hang very long without shrivelling.
Yet, when highly coloured and ripened early, there are few better keepers: we have known them amber-coloured in August, and cut and sent to table in March. Is it not therefore reasonable, and in accordance with facts, to suppose that many of our best late Grapes are capable of great improvement in quality by acting upon the points to which Mr Henderson directs attention? We think it is, and that the matter is one of very considerable importance in late-keeping Grape-growing. The palate generally rebels for a time at the flavour of such varieties as Gros Guillaume, Gros Colman, Barbarossa, Lady Downes, Trebbiana, etc, after Hamburgs and Muscats have all been used. These late varieties are very much wanting in the Muscat and vinous flavour of the Muscat of Alexandria and Hamburgs respectively. This deficiency, we are certain, might very generally be much improved or made up by the warmer and earlier treatment pointed out by our correspondent.
Take one or two cases in our own experience bearing on this point. We for some years forced our second house of Black Hamburgs to ripen in June. At the hot end of this house there was one "Vine of Black Lady Downes, which bore remarkably well; of course the fruit on it was left hanging on the Vine for many week? after all the Hamburgs were used. They generally hung through the heat of summer without the slightest signs of shrivelling, and sometimes were not cut till the Hamburgs were shedding their leaves. These Lady Downes attained to a degree of flavour which we have never known in that Grape in any other instance. Last year we had two rods of Gros Guillaume in a Muscat-house, one at the extreme cool end of the house, and the other close to the extreme warm end. The latter ripened at least a month before those at the cold end, and in October and Novernber were vastly superior in flavour to those on the Vine at the cool end of the house. It may be mentioned as another point not unworthy of consideration in this case, that the early-ripened bunches were from a rod grafted on Muscat of Alexandria; and our experience leads us to look on the Muscat as one of the best, if not the very best, stocks for other Vines; and also that this had perhaps a little to do with the flavour.
We think there can be no doubt that if Mr Henderson's suggestions were more generally acted upon, less would be heard of the coarseness of some of our otherwise very desirable varieties of Grapes. Some of the Blacks might perhaps not colour so well in a high temperature; but of coarse the house could be kept cooler while the colouring process is going on, and resumed for a time afterwards, for Grapes are not by any means ripe immediately they are coloured, especially the Black sorts; and we think it of importance that they should be subjected, to a high temperature and dry air for a time after the last touch of colour has been a .sinned.
It would, indeed, be singular if those late varieties of Grapes were not, like other fruits, beneficially influenced by the all-important agents, heat, light, and dry air - agents which render them more sugary, less watery and insipid, and consequently more agreeable to the palate, and more likely to keep well till spring. They are less likely to ferment, damp off, and shrivel when ripened comparatively early than when retarded; and, as is too often the case, ripened when light and heat have considerably declined.