You can't separate plants grown in rock wool since they quickly incorporate the wool cube right into the roots and base of the plant. One reason why onions and other root crops aren't commonly considered a rock wool crop since you have to sacrifice part of the edible root to get rid of the wool cube.. Are clusters bad? If you plan to harvest and use them as scallions, yes. If you don't care if they look like bulbs of garlic or shallots and are willing to sacrifice the immature ones attached around the core, fine. Dave

Joe wrote: "Hard to tell the difference even when two good plants are side-by-side. But amongst a group of 'DD Seedling', one can see the subtle variability." Thanks for the info Joe. Speaking of variability, that's one of my biggest complaints about Phormiums. More than once I've planted a grouping (3 - 5) of Amazing Red, Pink Stripe, or Sundowner only to have them grow in very differently ways - size wise. Very frustrating. I had high hopes for Monrovia's 'Festival Grass' Cordyline x 'Jurred' but found it works best with some afternoon shade. I assumed that being a Cordyline that it would be tough as nails but that isn't the case. Been using the other clumping Cordyline 'Electric Pink' with success so far, especially in containers.

Cat is right that the typically smaller growing, more colorful hybrids do not come true from seed, and are propagated mostly from divisions. I wouldn't recommend Phormium as an indoor grown plant, as they are very prone to mealybug even outdoors under less than ideal conditions, and need very bright light to grow well. People who grow these in the PNW sometimes may take them inside as container plants during the coldest spells, but they don't respond well to being keept in the dark and semidormant such as for Brugmansia.

Ooooh, I love this post. I recently moved to Colorado (Littleton) in late August from my home state of Michigan and was wondering where all the good nurseries were! There a few small ones by me. As for seeds, I like to order from Jung's, Baker Seeds, and Burpee (their catalogs, like most seed catalogs, have much more variety than what is sold in stores). I will also order from an odd catalog or two I get, but the ones I named are where I order the most. For live plants, I like High Country Gardens and David Austin. Four years ago I ordered one of Jung's perennial gardens for sun. They came in 3 inch pots and I wasn't sure they would make it through the Michigan winter. Three summers in, I had the most lush, beautiful perennial garden I could hope for. I will definitely take the gamble on Jung's perennial garden again once I find a permanent home in CO. At least I am in same zone here as I was in MI so hopefully I will have the same success!