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.
F. G-. says "What is the received belief as to the wearing out of varieties? My Early Rose Potatoes do not certainly do as they once did, and this seems to be true of other kinds. Is it not the same with fruits? Please say decidedly, will varieties wear out or will they not?"
[Yea, verily, varieties will run out, - and yet again they will not run out. If your potato patch has the potato stems bored by the Baridius, or the leaves badly eaten by the Doryphora, or blistered or burned by the Perenospora, or rooted out by the Homo before they are mature: or suffer in any way whatever injury to plant or foliage, though to all appearances the "murphies" may be excellent, there will be a certain running out in a few years. But if your Early Rose, or any other variety be perfectly sound and healthy, - if your potato plant goes on growing from spring to the autumn, unto in short its natural period of rest, flowering and fruiting its little seed apples, as nature intended it should, that variety will never "run out." They run out from perpetual accumulations of weaknesses, but not from anything in nature so far as we know. - Ed. G. M].