Edit 2/24/2024: At the end of the day, the big fact, that nobody bothers to say, that I didn’t realize, is that you have to harvest your mustard in the cool of autumn. I guess I should have taken a hint from the fact that North American Mustard Belt is in Canada. Restated, you can’t harvest mustard, in the summer, in Virginia. By that I mean you can’t get flavorful, evenly-cured, pleasantly-edible, good-looking mustard seed from mustard planted as a spring cover crop, in Virginia. Which is a pity, as mustard makes a dandy cover crop here.
Whether or not I can plant mustard mid-summer, and get a decent crop of pleasantly-edible seed in the fall, in Zone 7 Virginia, I will find out this year.
Edit 9/4/2024: This year I think I’m on the right path. I planted some common yellow mustard on July 1. It began flowering circa August 1. It’s just about done flowering, and has mostly set seed, as of September 1. And with any luck, temperatures will have dropped enough by the time it’s ready for harvest that I’ll actually be able to get nice, yellow, mature seed. We’ll see in another month or two.
Original post follows.
This is another one of those notes-to-myself posts. I’m just getting a bunch of facts that I need in one place, so I can’t lose track of them. In this case, the facts are about growing and harvesting yellow mustard in the home garden.
I only make two points in this posting.
First, I ought to expect to get about quart of mustard seeds from every 100 square feet of planted area.
Second, I should harvest yellow mustard well before the “dry and crispy” stage shown in most internet videos on this topic. Professional farmers either harvest it when the field is a mix of green-and-gold, seeds are all fully-formed but up to 25% remain green (for “swathing”, or cutting it to let it dry in the field). Or they can wait until all seeds are yellow and the moisture content is no lower than 12%.
Edit 3/8/2024: A good part of the reason you can’t harvest mustard, in Virginia, in the summer, is that the green mustard seed will NOT finish ripening in the Virginia summer heat. The heat destroys the enzymes in the plants required to finish maturing the remaining green seeds to gold. As a result, what is described as a standard technique for actual (Northern, fall harvest) mustard farmers (swathing) does not work at all in the middle of a Virginia summer.
Search this website for other posts on growing, threshing, winnowing and using home-grown mustard seed.
FWIW, this advice applies only to yellow mustard, not to other varieties.
Continue reading G23-027: Some further notes on growing yellow mustard in the home garden.