sow it under gravel, before winter.
For forced germination you have to sterilise and cut the pointed end off the seed, not just the aril. You cut off a slice about the thickness of a piece of good writing paper. There should then be a small hole revealed where the embryo can emerge. If you cut too much you will damage the embryo, If you cut too little the cut will heal and the embryo wont get through. It worked for me any time except the middle of summer. best to prepare by wetting and putting the seeds somewhere warm, then cutting and put them in the fridge in bags sterile and not too dry with perlite or vermiculite. When the embryos protrude put them in warmth to finish germinating, pot up in perlite and peat and keep shaded and cool + feed gently pot on with normal alpine compost and gravel when they are ready. They will keep growing for 18 months
