No, buckwheat does not come back year after year. When you ask is buckwheat annual or perennial, the answer is that it dies after one season. You must plant new seeds each time you want to grow it again.
I watched my first buckwheat planting die fast when the first hard frost hit in fall. The plants went from green and healthy to black and limp overnight. They never sprouted again from their roots the next spring. This showed me just how tender buckwheat is to cold weather.
The buckwheat life cycle explains why it cannot come back. This plant rushes through its entire growth from seed to seed in just 70 to 90 days. It sprouts, grows, flowers, and makes seeds all in one short season. Once it sets seed the plant has finished its job and dies even without frost to kill it.
Extension guides say buckwheat dies in winter. Cold below 32 degrees F (0 degrees C) kills it. Even mild climates get nights cold enough to kill buckwheat plants. You need fresh seed every year to grow buckwheat in your garden.
The one way buckwheat might seem to come back is through volunteer buckwheat plants from dropped seeds. If you let your buckwheat mature past flowering it will drop seeds on the ground. These seeds can sprout the next year and make it look like the plants returned. But they are new plants from seeds, not regrowth from old roots.
You can prevent volunteers by cutting your buckwheat at the right time. Mow or till the plants when about 75% of the flowers have opened but before seeds form. At this stage no viable seeds have dropped yet. Your next crop goes in without any surprise buckwheat popping up to compete with it.
I learned this lesson by waiting too long to terminate one patch of buckwheat. The next spring I had buckwheat sprouting all over that bed. The volunteers competed with my peppers and I had to pull them by hand. Now I always cut buckwheat before any seeds mature to save myself that extra work.
If you do see volunteers show up they are easy to control. Young buckwheat seedlings pull out of the soil with almost no effort. You can also hoe them down before they get more than a few inches tall. Or just let them grow as bonus cover crop benefit if the timing works for your garden plans.
The annual nature of buckwheat makes it a flexible tool for your garden rotation. You choose when and where to plant it each year. It does its job of smothering weeds and feeding pollinators for about six weeks. Then it dies and you move on to your next crop without any long-term commitment to that spot.
Read the full article: Buckwheat Cover Crop: Complete Growing Guide
