Haskap Varieties: Pollination and Bloom Timing Chart (Part 2)

This is the second part of the haskap series. In part 1 I described the plant and how to grow it; here I look at what decides the size of your crop: choosing varieties and pollination. More than a dozen varieties grow on my plot, so I can show how it works in practice. One caveat up front: flowering dates vary from source to source and from year to year, so the table below is a starting point, not gospel. Where data are uncertain or missing, I say so plainly.

Why one variety is not enough

Haskap flowers have both pistils and stamens, but the plant is cross-pollinated: each bush needs pollen from another, unrelated variety that flowers at the same time. Japanese sources describe haskap as strongly self-incompatible, and the yield of self-pollinated varieties is low (for the cultivar Yufutsu, self-fertility of about 28% is reported). It is pollinated mainly by bumblebees and solitary bees, because it flowers very early, when honeybees are still rarely flying. I write about helping bumblebees in my article on bumblebee houses (in Polish).

Haskap flowers up close. Photo by the author.

Four lines of varieties

• The Russian line (L. caerulea var. kamtschatica, altaica, edulis): Nimfa, Morena, Amphora (Leningrad group), Volshebnitsa, Chelyabinka, Sineglazka (Ural group), Yugana, Vostorg (Siberian group). They flower earliest and are the most cold-hardy (down to −45°C).
• The Polish line: Wojtek and Zojka, selected from seedlings of Russian varieties by Zofia and Hieronim Łukaszewski.
• The Canadian line (University of Saskatchewan): Tundra and Borealis (2007, Russian × Kuril hybrids), as well as Aurora, Honeybee and the Boreal series (Beauty, Beast, Blizzard).
• The Japanese line (L. caerulea var. emphyllocalyx, haskap): in Japan, among others, Yufutsu, Atsumamirai, Yushige and Mie, and in my garden Colin and Lori from Oregon. Details below.

How bloom groups work

Varieties are divided into early, mid-season and late bloomers. According to University of Saskatchewan materials, the bloom peaks of neighbouring groups are about 5 days apart. Very early and early varieties overlap for about 75% of the time, very early and mid-season ones for 25–50%, and very early and late ones usually do not coincide at all. A cool spring can delay flowering by as much as a week. All the Russian varieties tested in Canada flowered early, while the Japanese selections from Oregon flowered and ripened 1–2 weeks later.

Illustrative bloom order (not a calendar):
Early Russian: Nimfa, Morena, Volshebnitsa
Russian and Polish: Wojtek, Zojka, Amphora
Canadian: Aurora, Honeybee, Boreal
Japanese: Colin, Lori
earlier → later

Illustrative diagram: neighbouring groups overlap, but the extremes (the earliest and the latest) do not. Actual dates depend on the year and the location.

Haskap flowers grow in pairs in the leaf axils. Photo by the author.

The author’s variety list: origin and timing

I give the origin according to my own notes from the nurseries (where I could not find reliable data on a variety, I have marked this). Bloom groups and fruit data come from nursery catalogues, Russian variety descriptions and scientific publications. In a few places the sources contradict each other, which I have also noted.

The Japanese line: Colin and Lori

Colin and Lori come from a different line than most of my varieties. They are selections of the Japanese subspecies (Lonicera caerulea var. emphyllocalyx, known as haskap), bred in Oregon by Dr Maxine Thompson from seed brought from the island of Hokkaido. According to nursery and breeder descriptions, they differ from the Russian varieties in several important ways:

• Later growth and flowering. Russian varieties wake up easily during warm spells in February or March. Japanese ones flower later, so their flowers are less often hit by returning frosts. According to the University of Saskatchewan, the Hokkaido varieties are considered the best hope for warmer regions.
• Fruit. The berries are rounder or oval to barrel-shaped, firm and free of the bitterness typical of Russian varieties.
• Holding on the branch. The berries do not drop as easily as on older varieties, which makes picking easier.

Some sources note, however, that Japanese varieties ripen less evenly than Russian ones. Japanese varieties flower later than Russian ones, so they will not cross-pollinate with early Nimfas or Morenas. Colin and Lori should grow together or with other varieties of the same line. Maxin, Willa and Hoshi are varieties from the same American selection, sold by nurseries as “Polish-American”, but I could not find their flowering dates.

And which varieties are grown in Japan?

In Japan the first registered cultivar was Yufutsu (1992), large-fruited, productive and only mildly tart, intended mainly for processing. In 2009 Atsumamirai (tart) and Yushige (less tart) were registered; they pollinate each other. In 2012 came Mie, with firmer flesh and better keeping quality.

Example pollination groups

Based on the above and the rule “same bloom group, different varieties”, I arrange the bushes into several independent groups:

• The Canadian group (Boreal): Boreal Beast pollinates Beauty and Blizzard, so I plant these three close together.
• Aurora, Honeybee, Tundra: they pollinate each other in various combinations.
• Early Russian varieties: Nimfa, Volshebnitsa, Morena and Sineglazka flower earliest and produce plenty of pollen.
• The Japanese line: Colin and Lori, which flower later than the rest, form their own pair.
• The remaining Russian and Polish varieties: Wojtek, Zojka, Amphora and Chelyabinka form a second, slightly later group. Yugana and Vostorg make a good pair.

If you only have room for two or three bushes, go for a proven duo, such as Wojtek and Zojka, or Aurora with Honeybee.

How to check flowering on your own plot

The most reliable method is a notebook: every spring, write down the date of the first flowers and of full bloom for each variety, ideally over two or three seasons. The following year you can build your own table, more accurate than any catalogue. Do not plant bushes from the same parent variety, such as Wojtek seedlings, next to each other.

The first haskap flowers on my plot – 4 April 2026. Photo by the author.

When the berries are ready

According to the University of Saskatchewan, a berry is almost full size about 4 weeks after flowering, completely dark blue after 5, and fully ripe after 6–7 weeks. Ripe berries can hang on the bush for about two weeks. A dark blue colour does not yet mean full ripeness, because the flesh can still be green. More on harvesting and preserves in part 3.

Berries as they ripen, changing colour from green to dark blue. Photo by the author.

Sources

• University of Saskatchewan: Haskap bloom and ripening charts; How far south can haskap be grown
• Tanie Rośliny: Jagoda kamczacka Mailon (in Polish)
• Akademia Roślin: Zapylanie jagody kamczackiej (in Polish)
• Polisadnik: Сорта жимолости съедобной (in Russian)
• Japanese Wikipedia: ハスカップ
• e-katalogroslin.pl: variety profiles for Wojtek, Zojka, Nimfa, Morena, Tundra (in Polish)
• Drzewa.com.pl: Jagody kamczackie (in Polish)
• In-vitro.pl: Colin PBR (in Polish)
• Art's Nursery: Haskap varieties information
• Growing Fruit forum: Haskap bloom timing

This article was originally written in Polish and has been translated into English.

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This article comes from my blog Laboratorium Natury (“Nature Lab”), where I write about my garden plot in Poland and a more self-sufficient life. It was originally written in Polish and translated into English. Full version with photos: https://jaworznia.pl/en/2026/10/28/haskap-varieties-pollination-bloom-chart-part-2/