Here in Ladakh, Lepidium latifolium is native and is traditionally eaten, but in the US it is apparently an invasive weed in many places. If you've got an infestation near you, here's how to to get a bountiful yummy free harvest. It does take two days of waiting, but it makes a rich smooth cooked green.

It is one of the earliest plants to appear in spring (probably because it is shooting up from its rampant, thick and deep runner roots). Pick about 4 - 6 inches of the top when the whole thing is between 4 and 10 inches tall, or until it starts to form tiny flower heads. The stems may be a little thick but you will find that they are still tender. Pick a lot, because with boiling they will shrink down, and you will like them and want more. Throw them into a pot of boiling water for a about five minutes, until they change color to dark green, and a strong bitter mustardy smell fills the kitchen. Now drain them and dump them into a pot of fresh water, and leave them overnight. Tomorrow, taste a leaf. If it is still bitter, change the water and soak it another day. Ours is sometimes delicious after one day, and sometimes takes two. When the bitterness is gone, fry it in oil, butter or other fat, just as you would spinach or any other green. We find it smoother and richer than other greens.

Since pepperweed is so abundant, and since we have few fresh vegetables in the winter, we dry a lot of it. We simply pick the shoots and strew them out to dry in the sun. In winter, we follow the same process: boil for 5 min, then soak overnight; and it usually only takes one overnight then.

The exact same method is used around here for caper shoots (Capparis spinosa), which are even more delicious but not nearly as plentiful, and not listed as an invasive anywhere. Boil 5 minutes, drain, soak in fresh water a day or two, and then fry up: YUM!

Both of these greens are traditionally eaten with chapattis for breakfast here, and I must say it's a compulsively satisfying habit.

Stopping the bus with all our students for 15 minutes twice in May, we collected sacks and sacks full to dry for the winter. Yay Lepidium!

Collect about 4 inches of tips, leaving bigger leaves behind unless you want to weaken the plant

Lepidium latifolium is also edible at my hometown in China.

Bumping this in late April, the season for collecting perennial pepperweed here.

An article about the nutritive value of Lepidium latifolium:

Results showed that this plant is an excellent source of glucosinolates, notably sinigrin that is present in very high amount (~70–90%). Its value ranged from 149 to 199 µg per g fresh weight. Fatty acid composition analysis showed that its leaves were abundant in unsaturated fatty acids, specifically linolenic acid (18:3) whose percentage is about 50%. Higher glucose and crude protein along with higher nitrogen to sulfur ratio, supplements the nutritive value of this plant. Based on total phenol, flavanoids, free radical scavenging activity and DNA protective activity showed that this ecotype of perennial pepperweed contains high antioxidant properties. The percentage inhibition for O2− scavenging activity ranged from 41.3% to 83.9%.

Here's our second batch this year, having been boiled for 5 minutes and now soaking in a fresh change of water for a day.