These are just some random, and somewhat obvious, thoughts I've had while working at the nursery. (Many thoughts have had to be cut. I'm trying to stay positive here.)
Skunk cabbage has a tuberish thing with long roots that are mostly unbranched, rubbery things that have rings like annelids, but more closely spaced. Reminds me of mandrake (isn't that the screaming plant in the first Harry Potter movie?).
Weed pots, especially weed out alders and willows before they become full size trees! The trees can be salvaged, but the root systems are bound and usually lopsided, while the intentional plant is nearly dead or dead.
Wind barriers are very important at a nurery with trees. Stakes are important too, but make sure you don't buy stakes that need support themselves. Oh and invent something that will keep treepots reliably upright. Unless you are going for bonsai materials, don't let young trees grow crooked. And nearly all trees should be single-trunked, if you ever want to sell them.
Soil sterilizer, I wish I had one. But is there not a low-tech alternative? My faith in the composting process isn't that strong. I have a compost pile that I completely neglect. Composting is a real weakness of mine!
Seed propagation. It surely must be the noblest form of propagation. Must become a seed master. I do not like wild collecting, especially on a large scale, especially for profit. I don't mind taking a snip here or a seed capsule there.
Wouldn't it be cool to have woven old-english stlye fences everywhere? With a hedge of wild roses and hazels behind it? And geese running around keeping the grass down? Old England meets native California culture and plants. This is the Garden of La Mancha.
Organization on the grounds and in the books is "importante" for a business. So are clean, sharp, tools. Yes tools. You know, I really would like a scythe. Why don't we use them anymore? I also would like a pruning knife. And a watering can with a rose attachment.
All by-products need to become products. When I coppice my grasses and rushes this year I'll have native straw for mulch. Some of the "weeds" (only the natives) can be potted up. Things must be reused. Close the loop!