January 31, 2010

A weed by any other name, Primula malacoides

In the fine Timber Press book PRIMULAS, the monster monograph on the genus primula by John Richards, one can discover that the lovely florist flower we sometimes find in better greenhouses on these short day-length winter days Primula malacoides was considered a lowly weed. According to turn-of-the-Century plant explorer George Forrest, " P. malacoides is clearly an abundant field weed in these localities of Dali, Lichang, Tengyueh and Yunnansen" . Yet, as abundant this "weed" apparently was in 1900, today, modern cultivation methods may have rendered this man-dependant species very rare in the wild.

First flowered in cultivation from seed collected by Forrest in 1908, the species of P. malacoides was quickly adopted by commercial seed growers in England, and within a decade, became a fragrant,colorful strain sold in the cold greenhouses of Europe and the United States. Many named strains were introduced in the early 20th Century, and suddenly, Primula malacoides became one of the most popular pot plants for conservatory culture, especially since it is primarily a winter grower, and, profitable for commercial growers, since it's roots of once being a weed in the rice fields of China, meant that it was indeed and annual, so new crops would need to be grown each year, to fill the plant windows and conservatories in the winter.

Today, the species is less common, being short-lived in our hot, dry modern home climates, and this species, along with it's companion species which shares the same growing season, Primula obconica, shares the trait of having primulin, a chemical in all primula species, but particularly irritable in these two species to a few people who are allergic to it. For some simply touching the hairs on the leaves of these two species, may cause a dermatitis or an itchy sensation not unlike poison ivy, but can cause a severe rash headaches or nausea. This has been somewhat bred out of newer hybrids, and relatively few people have a severe reaction.

Primula malacoides is an annual that blooms in the short days of winter, so seed must be sown in the greenhouse in June or July, if one wants plants for January. Most growers today use a peat based soiless mix, but many experts prefer a loam based soil. This is a plant that should never be allowed to dry out, and it prefers a buoyant, moist cool atmosphere. If you happen to find a plant of this Primrose, it may be best to pot it up into a larger clay pot, for the 4 inch plastic pots that commercial growers use are unsuitably small, and dry out in a day or two. I repot store bought or nursery bought plants into 6 inch clay pots, and let them sit in water once or twice a week.

Primula malacoides grows in Burma, and Sichuan at 5000 ft in meadows and damp fields, so take a lesson from it's native haunts, since it grows wild around the mounds and shores of rice paddy's. There are related species which have completely fallen out of favor in commercial horticulture, P. forbesii which was introduced by Vilmorin of Paris in 1891. Reportedly, this species was common in spectacular winter conservatory displays in Paris around 1900, with pink blossoms virtually covering the plants in massive plantings underglass. Today, I have yet to find it.

This weekend I found some P. malacoides at a local garden center, and I grabbed one of each color. We hosted a meeting of the New England Primula Society on Saturday for a luncheon, and I needed some Primroses since this year I did not grow any. These potted plants are so fragrant, that it felt like spring as soon as you walked into the greenhouse. I've been looking for my favorite, but rarely grown florist primrose, Primula obconica, but could not find them again, anywhere. But the nursery where I bought these, had seen some at the Boston Flower Market, and promised to buy a case for me, for next weekend, I cannot wait.

Last year, while in Japan during February, I saw incredible cultivars of both P. malacoides and P. obconica, both distributed by Sakata Seed, but not available here, in the US.


  1. I stopped by to see what was growing on your blog today. lol Sorry bad joke but an interesting post.

  2. Otherwise, you have to wait until they grow into something you recognize before you thin them out. ​herbal pen vaporizer

  3. I bought a packet of P. malacoides (Fairy) in Australia in January 2015. Seeds were planted in peat disks upon my return to St. Louis. They were transplanted to larger pots and continue to expand in size. I have too many now to bloom in the house over winter. Can I plant them out in cooler autumn in a wet, shade bed, with a trop dressing of mulch and expect them to flower after the last April frost. We are in Zone 5 overlapping with 6.


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