With the input of other participants in the Organic Seed Partnership, Cornell breeders crossed Boothby's Blonde to Marketmore 97, a long green cucumber and the newest cucumber in the Marketmore line. Marketmore is highly praised for flavor and disease resistance. Yes, it laughs at fungus diseases that can cause the vines of an ordinary cucumber to wither during cooler and wetter weather especially.
I received the packet marked with the breeder's working number NY04-722-N (Marketmore 97FF x Boothby's Blonde) F2. I suspect that the F1 hybrid resulting from the original cross probably produced only green cucumbers since green color is dominant in cukes. The F2 seed I received resulted from the crossing of two of those hybrids. So, out of this second generation seed, I should see a percentage of plants producing the recessive white trait in cucumber skin color. My job since I volunteered, was to select a perfect Boothby's Blonde. A disease resistant plant that keeps on turning out little creamy white cucumbers all season long.
One of the Cornell Crosses that we continue to work with at Flanders Bay Farm is indeed the selections we made in 2005 from NY04-722-N. Why? You see, this was a cross of a New England heirloom favorite, Boothby's Blonde, a handi-sized white snacking cucumber acclaimed for it's mild flavor and crunchy texture. Those that like white cucumbers for novelty and flavor appreciate the Blonde. Fedco Seeds, a seed cooperative that is a major seller of seed to organic farmers in the northeast have sold Boothby's for many years and the stumpy white cucumber has a loyal following. What would be better for organic farmers selling for market though might be more productivity and disease resistance. If only those vines would keep on cranking out cukes like the disease resistant Marketmore.
A Disease Resistant Boothby's? So far, the vines are healthy and the yield is much better than the original Boothby's Blonde that we are growing for comparison. It's always nice to be able to compare what you hope is an improvement to the original. You can see that the fruit is a bit more streamlined than the original. It has a nice length to width ratio that picklers look for. It also has a pleasant fresh eating quality. It's black spined like the original.
The siblings of the F2 Boothby's Blonde Cross (Boothby x Marketmore 97) produce loads of mostly striped yellowish-green kirby-sized and shaped fruits and the white fruited kinds that we want. Interesting, the dominant green trait was not the uniform dark green of the Marketmore parent. Since we're only selecting for "whites", we pick off the male blossoms and nip back the vines of these so they do not cross with the white. We'll let the bees do the crossing of the white. The fruit that result from developing females on the non-white sibs will make great salads and oh yes, we'll let some mature for seed because they do have great genes from the outstanding Marketmore 97 and the little heirloom from Maine. The seed will also produce quite a few white fruit since they carry the recessive white genes and will cross with the white selections.
The vines in 2007, now in the third year of selection show great promise. We still select for the traits that we like. They are still bee pollinated and so we waited until we were certain that there were all white fruited in our patch (by watching as they produced their first fruit). If there was just one green fruited plant then we would have had to remove the vines of the green type and also all the fruit and female flowers already growing on the white vines. These female flowers will produce white cucumbers but they could have crossed with the green plant which we are selecting against. New flower buds that open will only be of the pure white genotype and can then be harvested for white fruit in the future. It is a bit of work to go through the vines, one plant at a time to make sure that they are all producing white fruit.
Most plants in 2007 produced stubby creamy yellow fruit but one plant produced a fruit which looked a bit like a white variation of Marketmore 97. A nice looking cucumber with a the very good Boothby flavor and good disease resistance.
The over-ripe fruit of black spined cukes such as Boothby's Blond turn orange when they are ready for seed harvest. We allow them to start to rot and ferment in a tub so that the gel around the seeds break down and we are able to wash the seeds. The good seeds are heavy and sink allowing one to float all the waste off. If there is sill some attached gel, lay a single layer of seed on a small mesh screen and use a forceful stream of water to remove the gel. It usually works for us. Then let the seed dry on the screen. When the seed breaks with a snap (does not bend), it's dry enough to store in a sealed container.
Other White Cucumbers
This is a modern Italian White Cucumber. Seeds of white cucumbers were in commerce in the 1700's and probably before that. They had names like Turkish White, Dutch White and Paris Long White. In America solid green dark green ones were favored but in Europe especially, white cucmbers were popular especially for pickling. The Far East also have pure white cucumbers and pale green or white grading into green kinds.
"Miniature White" is smaller than "Boothby Blonde", only 2-3 inches when at the eating stage. It's marketed by the Seed Saver's Exchange, Decorah, Iowa. It rapidly swells with seeds though and turns orange when it's mature for the seed saver only a few days later (not illustrated).
An interesting white cucumber from Korea. Bright white fruit are long and wide and are fine slicers. It is a white spine type.
White cucumbers are probably better known in Europe and Asia where they are used in cooking and pickling. We're just beginning to see some of Asian varieties appear in retail seed catalogs. White Stallion comes an importer of asian seeds, Dimension Trade Company, Scappoose, OR. It's a real beauty. The fruit of the one above is about 9 inches in length, comparable to an American market type. It is a vigorous climber although we use cucumber clips (to right of the fruit stem above) that snap the vine to the netting so that the weight of the fruit doesn't pull the vine down. It's also a good greenhouse variety and produces large numbers of consistently marketable fruit but also does well in ground culture.