Longjohn Plum

Overview

A newer plum for us, Longjohn is a European-type plum developed at Geneva, New York, and introduced in 1993.

History & Parentage

According to the most detailed cultivar record we found, Longjohn’s parentage is Iroquois × CA4A33L; it originated in Geneva, New York and was introduced by NYSAES breeders including R.L. Anderson and John P. Watson. It was named in honor of plum breeder John P. Watson.

Fruit Quality & Uses

Longjohn is a large, long/teardrop-shaped blue plum with amber flesh, freestone, and high eating quality in the “European plum” style. We've only ever eaten it fresh but it is also commonly used for jam, baking, canning, freezing, jelly, sauce, and it’s noted as suitable for packing/shipping.

Growth Habit & Spacing

The tree is vigorous, upright/spreading, somewhat willowy, precocious, and productive. Spacing should follow rootstock; as a practical range: ~12–16 ft on semi-dwarf plum rootstocks, ~16–20 ft on vigorous/standard. We only have Krymsk 86 as a rootstock, for which you can go 15 ft. spacing with some pruning, up to 18 ft. with less pruning (and if you're working in deeper soils), or even possibly tighter than 15 (down to 12 ft.) for tighter and more managed growing systems.

Pollination

It’s described as partially self-fruitful, but heavier crops occur with a pollenizer; suggested partners we offer include Stanley, Italian, Northern Blue, Mount Royal, Mirabelle de Bitterroot, and Yakima.

Cold Hardiness

Many sellers market European plums in the general “around Zone 5” band, but that’s not the same as a documented absolute minimum temperature for this specific cultivar. Bob Purvis lists it as hardy to -35F, which would put it on similar footing as Italian plum and other Europeans. Zone 3b.