I bought the 1976 classic Seed Starter's Handbook this year because I wanted to try my hand at growing annuals and veggies. There's several pages dedicated explaining the advantages of using sea kelp for vegetables. So I think the idea that it produces useful effects has been around for a while. As Dr Don points out, in addition to potassium and trace minerals, it has a few organic chemicals that are believed to help plants grow and fend off disease.
I'm afraid I have been so focused on stopping critters from eating my plants whole that I've not yet spent much time spraying them with Messenger, Sea Kelp, Agroflash, or any of the other miracle sprays that grow tomato plants the size of redwoods and peas the size of watermelons.
I do have some roses that could use a boost that fertilizing with rose food has not supplied. So thanks for the heads-up, Toni!
