Most of my usual Monday content was covered on Bloom Day, so instead, I offer a take-down of seaweed extracts by Dr Linda Chalker-Scott (of the Washington State University Extension and the superb Garden Professors blog).
Specifically, I offer it in honour of Seaweed Extract Guy, who has cornered/accosted me three times in as many months at the local garden centre to recommend that I use a liquid seaweed fertiliser for everything from soaking my seeds to feeding my herbs to spraying my houseplants.
I understand; his job is to move product. But when any one product is recommended as a miracle cure for slow seeds, hungry herbs, and allegedly bug-ridden houseplants, I am suspicious.
My handful of houseplants, for the record, are healthy and do not need spraying. They need me to remember to water them.
I am not a scientist, but I am pretty sure that moving the herbs into good garden soil or potting mix and giving them sufficient room to grow will do as much for increasing their size as regular doses of seaweed extract.
There might be something to the seed-starting advice. As is noted in above take-down, "seaweed extracts contain plant growth regulators which, like traditional rooting products, can stimulate root growth in cuttings and transplants." That is to say, it might be worth testing if those plant growth regulators have any measurable effect on germination or seedling growth, too.
It is entirely possible they do not. Only 'doing the science' would tell us for sure. In the meantime, I'm going to wait to see if the snake squeaks before I buy oil for it.