Siberian Poppy / Linnaeus Poppy (Papaver nudiacule)
This variety was discovered in the late 1750s and has been described by our very own Carl Linnaeus. This hardy poppy is said to be able to withstand temperatures down to -29 C. In the wild it comes in yellow or white colours and the variety originates from the subarctic areas of the globe. Do not confuse with Papaver croceum.
With its silky, paper-thin, crinkled petals in varying colours from white, yellow, orange and red to the now more pastel soft tones of pink, coral, apricot and cream, it makes a lovely addition to an early summer wedding or event. There are several varieties, with the fuzzy stems reaching a length of around 30-75 cm.
The linen poppy is the one of all the poppies that is best suited as a fresh cut, provided you are quick at harvesting, which I will return to below. It is a short-lived perennial that is usually seen as biennial, for safe harvesting in a cut flower cultivation, the flower is grown as an annual, ie you sow new ones every year.
If you want to challenge yourself and above all your patience, then the linen poppy is an option for you. It is a tenacious performer that takes its time. Allow a month or so before you see the character leaves emerge and allow the same amount of time to plant out.
Is it difficult to grow?
The linen poppy is not a beginner’s flower, but having said that, it is really rewarding when you succeed! My hope is that this text will help you on your way. The seeds are small and the sowing requires some care at the beginning, once planted out they deliver plenty of stunning flowers that at least I can’t get enough of!
Remember – there’s a difference between poppies and poppies. Unlike most other poppy species, linen poppies are pre-cultivated, but like the other species, they have a delicate root system.
If you live in the south of the country, it may be worth trying outplanting in the autumn, for overwintering and flowering in the spring. This text is written based on cultivation zone 2-3 (Stockholm), which may be useful to keep in mind.
Sowing:
Siberian poppies have a long development time of about 16 weeks and they want a long period where they can grow cool, so it is of utmost importance to start sowing early in the season, already in January, at the latest February. It’s a shame to spend so much time and effort on a flower if you start too late as they can’t cope with the summer heat.
As they are quite fragile, like many poppies and especially the roots, I strongly recommend propagating in soilblockers or similar. Cells from the plug tray can be an alternative, however, I have not tested myself while broad seeding is discouraged. Another advantage of sowing in soilblockers is that they get the right volume of soil from the start if you start them in micro 20.
The small seeds are best sown using a toothpick (moisten the end that will move the seeds) and they should not be covered, but need light to germinate optimally. If you want to improve moisture and keep them in place more easily, you can sprinkle a thin, thin layer of fine sand or vermiculite on the soil surface, but not with soil.
After sowing, the surface is covered with a lid or plastic/glass and ventilated daily. Good air circulation is always desirable when sowing. Optimal germination temperature is 15-21 C. Given the small size of the seeds, water the sowing from below, otherwise you risk accidentally washing them away.
Within 1 week they should have germinated. Remove the lid/plastic/glass at this point. After about 3-4 weeks it is time to retrain, I put them in a larger soilblocker and move them to a cooler space, temp of 10-13 C rec here. They do not like temperatures above 21 C and produce poorer flowers at higher temperatures. Worth thinking about when choosing a final location.
Think of careful handling when retraining, as always you hold the character leaves and not the stalk or roots (unless you have a soil cube to hold). If you can’t or don’t want to let them grow on at the same size, don’t forget to start nutrient watering at this time. Linnaeval poppies don’t do well if they are left to stagnate before planting out, so remember to allow a maximum of 10 weeks.
Planting out:
The timing of planting out varies, with some growers, especially in milder climates, planting out after 1 month while others after 2 months. I myself run on the latter range, around 1.5-2 months depending on how well developed the plants are and how the spring is. It is worth mentioning that they are not large at this stage, the proper growth occurs after planting out. Before that, it is mainly the roots that I want to develop and stable leaf pairs.
Harden off before planting out, they can withstand light frost but use fibre cloth as protection in the beginning. Plant distance 20-30 cm. When they are about 2 months old, I plant them out in a cold greenhouse in the first place. Some I put out later outdoors in temporary growing tunnels, which I can easily remove when the early summer heat comes. The growing site should be well-drained, a big plus if the location is sheltered.
The advantage of tunnel greenhouses is that the flowers are protected from rain from above, irrigation with a drip hose is recommended otherwise root waterers can be an alternative for the smaller cultivation. The disadvantage in cold greenhouses is if the temperature gets too hot, as they thrive best below 15 C.
If you can protect them from slugs it is desirable, which are the main threat although they seem to favour tender lettuce leaves and young sunflowers as examples.
Harvest:
Linnaeus Poppy produces a harvest until night temperatures rise above 15 C, you can expect about 10-15 stems/plant. When it comes to harvesting, you have to be quick, a flower can go from closed to fully open in 50 minutes (I have clocked).
When the fuzzy bud starts to open and you can hint at the colour of the petals, it’s time! This usually happens in the morning but get into the habit of going through the poppy at least 2-3 times/day (assuming they are for sale, otherwise enjoy).
The sheath also protects the fragile petals from the weather. Sometimes the flower may need help to get the whole sheath off, the petals will unfold themselves so leave them alone. If you harvest too early, some flowers will not be able to open themselves.
When harvesting, the end is burned for about 10 seconds after cutting, and then placed in cold water. The alternative is to dip the end for 10 seconds in boiling water, but personally I find it easier to take a lighter out with you. This is repeated every time the end is recut.
If the flowers are to be transported, they are best packed with part of the bud left (albeit slightly opened). This can be carefully removed yourself. Fully open flowers with their fragile petals are less suitable for transport.
How long is the vase life?
5-7 days, shorter if harvested when the flower has opened. Best shelf life is in the fridge keeping around 4 C.
How do I best store the seeds?
Seeds for Siberian poppies are best kept refrigerated and should keep for up to 4 years.
Author: Natalia from dengodafloran https://dengodafloran.se/
Fact-checked by Erik Hoekstra
Last updated 2024-02-15
Natalia, who runs ‘den godafloran’, is a trained gardener, cut flower grower and previously a registered veterinary nurse.Natalia has several interesting articles on her website and she has online courses in cut flower cultivation.