Hi, I'm new to this forum. I've been trying to grow dragon fruit from seed. I get them to sprout easily and they appear like "Y"s. However, they get stuck there and won't put out spiny growth. I've fertilized them and cared for them, but I lose interest after several months of no growth. I have used grocery store dragon fruit without the irradiation symbol, but wonder if they might have been irradiated anyway. Any suggestions?