Growing Lapageria rosea from seeds
Lapageria seeds are short lived, they are born in a soft fruit and should be planted before they dry out completely. For this reason I don't dry them and always store them moist with a small amount of their own pulp and juice on them. After some time a bit of a black mould could develop on the pulp, this is a natural process that does not infect the seeds and nothing to worry about - you can just wash it away gently with some lukewarm or cold water.
For the sowing use acidic peat moss (pH 5.0) or finely milled pine bark mixed with lime-free sand and perlite. Seeds should be buried under a layer equal to their own diameter. Expose them to fluctuating low temperatures between light freeze and +10℃, or place the whole pot in the fridge at temps about +2℃ to +4℃ for about a month. This process is called cold stratification and I start it right after I harvest the seeds by placing the whole fruit in the fridge. So depending on when you purchase the seeds they may already have been stratified and you can proceed directly with the next step. Please message me and I'll let you know about the exact batch you received. After the cold stratification the sowing should be moved to a cool place with temps between +10℃ and +20℃ until the seeds germinate. Keep the substrate evenly moist and ensure good ventilation.
Initially the seedlings grow very slow and long periods of time may pass without any visible activity. Such growth and rest periods are natural for adult plants too. It is important to maintain the seedlings in a cool, humid environment with lots of fresh air. Warmer day time temperatures should be compensated with a significant temperature drop at night. Bright light but no direct sun, constantly moist, very well-drained, acidic, lime-free soil, guarding against aphids and any root damage are very important factors.
Adult plants prefer some direct sun in the morning or the late afternoon, but should be carefully acclimatized to it. New growth is very tender and easily damaged by pests, strong sun, heat and drought. Leaves persist on the vine for several years so any damage done to the new growth will be quite lasting.
Mature plants can take a brief frost down to -5℃ for several hours during the night. In colder climates grow them in pots and overwinter inside.
I grew my stock plants from seeds and saw the first flowers on the third year. So with the right care and optimal conditions you can expect the first flowers 3 years after germination, otherwise you may have to wait much more.
I am sure you will enjoy some more photos of my plants here.
I wish you success in growing the beautiful Copihue!
Author of the text and photos: Petar Kostov, telopeanursery.com, 20180716, edited Oct. 2019.