I can't recall why I first decided to try growing asparagus peas (Psophocarpus tetragonolobus). Maybe because I've always loved asparagus -- and these pods do, when young, have a mild asparagus flavor.
They're also one of the simplest vegetables you can grow -- if you have some space. That's a polite way of saying that this is an aggressive plant that would enjoy taking over it you let it. On the other hand, if you have a spot to let a 10-foot vine with pretty pale blue flowers (and unusual-looking pods) do its thing, it's a great plant.
Like most-edible-podded peas, it can be started a bit before the last frost date in the spring, which is when most gardeners are itching to plant something -- anything! -- that doesn't require hot weather.
At least, that's my experience (and it appears to be the experience of Geri Harrington, author of "Growing Chinese Vegetables in Your Own Backyard," a book I really like). But some places on the Web say it needs warmth and shouldn't be planted till all chance of frost is past.
The problem with that is that the plant flowers only when daylight is less than 12 hours daily. So if I waited till the end of May to plant, I'd have only a couple of weeks before days were longer than 12 hours. In USDA Zone 8 or 9, it makes a nice fall crop.
To hasten germination, you may want to soak the seed overnight in water or scarify the seeds.
Among asparagus peas' advantages: They aren't fussy about soil, they begin bearing in less than two months after sprouting, and all parts of the plant are edible (leaves, flowers, pods, even the roots). Ms. Harrington says the pods are high in protein.
The frilly pods are best picked when small -- say, less than 4 inches long. In high season, you'll be harvesting daily.
There is quite a bit of common-name confusion surrounding asparagus peas. There's also an asparagus bean (yard-long bean) and a different species (Lotus tetragonolobus) that goes by the same common name (it has pretty red flowers instead of blue ones). Other common names are winged peas, goa bean, asparagus bean, princess pea, four-angled bean, short-day asparagus pea, and various Chinese names. Make sure you get Psophocarpus tetragonolobus.
The end of their season has arrived in my garden. But it was a good one: I served my abundant harvest plain as I would snow peas, included pods in stir-fries and Asian dishes, added blanched pods to salads, and used the blossoms for garnish.
I've never tried the roots, but Harrington's excellent book says they can be cooked "any way you'd cook a sweet potato." Maybe next year.
When you serve them to anyone who's never seen asparagus peas before (they grow throughout Asia), you'll gets lots of funny looks -- and questions. Unless you're in an ethnically diverse neighborhood, you'll probably be the only one growing them. But that's OK – the others are missing out on something unusual and definitely easier to grow than asparagus.