Published by Brian Wagner on 10/24/25 in “Growing Flowers from Seed.”
Primula alpicola (commonly called moonlight primrose) can be found growing in moist alpine meadows of the Himalayas. It is special among the Primulas for its color range and its flowering season. Natural color variations include cream, violet and periwinkle – and they flower in the summer. Most primroses flower in the spring, making P. alpicola unique indeed.
Hardy to Zone 4, it is a tough plant – but it prefers moist soil above all. It will even grow in part shade as long as its moisture needs are satisfied. It has a strong preference for riparian ecosystems in its native Tibet/India, typically growing in saturated silt or clay soils in wet alpine meadows. It is a perennial, and with adequate moisture and cool summer temperatures it will form dense colonies over time.
Growing from Seed
A few key studies reveal its dormancy and germination behaviour. Its seeds have a non-deep physiological dormancy, which means that they require a cold moist (i.e., winter) period before they germinate but the period is rather short. What’s clear from the research is that seeds have a cycling behaviour – they come out of dormancy after winter, but if they don’t germinate in the spring then they re-enter dormancy in the summer (i.e., due to the heat). This kind of ‘cycling’ in and out of dormancy is common for seeds that have a non-deep PD. Field Poppies behave in the same way.
To break dormancy and propagate fresh seeds, it is best to cold stratify at very cold temperatures – just above freezing – for about 6 weeks. Find the coldest part of your fridge (often at the back and lowest shelf, such as the crisper drawer). 6 weeks has been found to be ideal (Wang et al, 2017), whereas 4 weeks is too short and 8 weeks is too long. Seeds must be imbibed with some water in order to achieve cold stratification, therefore place seeds wrapped in a moist paper towel or cloth (inside a container or thin ziplock bag of some kind).
After, incubate the seeds at 20C (~70F) during the day, but you need to keep the seeds cold at night – back in the fridge! Repeat this in/out cycle every day until seeds start to germinate. Seeds are also quite indifferent to light, so you don’t need to place them under grow lights to induce germination. Seeds should germinate in about 6 days.
If you’re using older seeds that have been stored at room temperature for 6-12 months, you might try skipping cold stratification and simply sow them as per above. If they don’t germinate in a week, then toss them in the fridge for 6 weeks.
References
Baskin CC, Baskin JM. Seeds: Ecology, Biogeography, and Evolution of Dormancy and Germination. Second Edition. 2014. Academic Press: San Diego, California
Hitchmough J, Innes S, Mitschunas N. The effect of seed treatment and depth of sowing on seedling emergence in Primula species. Seed Science and Technology. 2011 Oct 1;39(3):539-51.
Wang G, Baskin CC, Baskin JM, Yang X, Liu G, Zhang X, Ye X, Huang Z. Timing of seed germination in two alpine herbs on the southeastern Tibetan plateau: the role of seed dormancy and annual dormancy cycling in soil. Plant and Soil. 2017 Dec;421(1):465-76.
Wang GuoYan WG, Baskin CC, Baskin JM, Yang XueJun YX, Liu GuoFang LG, Ye XueHua YX, Zhang XinShi ZX, Huang ZhenYing HZ. Effects of climate warming and prolonged snow cover on phenology of the early life history stages of four alpine herbs on the southeastern Tibetan Plateau. American Journal of Botany. 2018; 105(6): 967-976.
Wang Y, Xu Y, Jia C, Hu X. Reconsidering warming effects on seedling recruitment in Tibetan Plateau’s alpine meadows via open‐top chamber experiments. Journal of Applied Ecology. 2025 Apr;62(4):884-98.