In The Garden With KokHeong: Perennial Vegetables

Los Alamos

What gardener wouldn’t like the idea of planting a vegetable once and having the plant continue to produce year after year! There are quite a lot of these perennial vegetables that do quite well here, asparagus being one of them.

Although they can be grown from seeds, asparagus are best started from crowns. It usually takes about 2 years before the shoots can be harvested, and even then, sparingly. I let most of the shoots grow into ferns in the first couple of years in order for them to establish a healthy root system. Asparagus is one of the first vegetables to appear in my garden, ready for harvesting in late spring and early summer. There are male and female plants. The female plants produce berries and they are more susceptible to asparagus beetles. Many commercial growers grow only the male plants, but I don’t mind having a mix. The seeds can be winter sown in jugs to produce new plants. I leave some of the berries with seeds as winter food for the birds.

Another early perennial vegetable is sorrel. The young leaves are a bit sour and can be added in small quantities to salads. Cream of sorrel soup is one of our family’s favorites. There are many kinds of sorrels – large leaf sorrels, red vein sorrels, Sheep’s sorrels, to name a few. They all do well here.

Other perennial vegetables that grow well here are Jerusalem artichokes (or sun choke), rhubarb, and horseradish.  They propagate easily by sending out new shoots through their root systems so they tend to take over the entire garden if not cut back regularly. Unlike rhubarb, whose leaves are poisonous, horseradish leaves are edible. The young leaves are especially delicious and taste like mustard greens on steroid.

Many herbs are perennials – tarragon, chives, rosemary, thyme, oregano, sage, borage, lovage, garlic and Egyptian walking onions come to mind. Others like parsley, cilantro, basil, and dill are annuals but they self-seed so easily that once established, they come back year after year as if they were perennials. My very favorite perennial herb is garlic chives, which is used as a vegetable in Chinese cooking. We use them chopped up as pot-sticker fillings and scrambled with eggs for a side dish that I playfully named “Green Eggs Without Ham.” We also cut them into inch-long segments for soups, and add them to Ramen and other stir-fried dishes. They go particularly well with shrimps, one of my favorite stir-fried dishes. Many cooks use it to “season” a new wok by stir-frying them with a bit of oil until they are quite burnt, so as to “break in” the wok. The burnt garlic chives are then discarded. Garlic chives’ flower buds (before they open and the sepals can be quite though) are especially valued and they sell for three times as much as their leaves. Their clusters of tiny white flowers are attractive to bees and can also be harvested for making relishes and pesto. Their seeds can be grinded into a paste with olive oil for a strong and pungent spread on toast, if you like that sort of thing.

Egyptian walking onions are named for the way they propagate. They don’t produce large bulbs underground like regular onions, but produce long stalks with small shallot-sized bulbils at the tips. If left alone, the tips get so heavy that they droop over and the bulbils reach into the soil to grow a second cluster of plants about a foot away from the mother plant. This continues for the 3rd and 4th clusters so that it looks like the onions “walk.” I use Egyptian onions in 3 different ways – the young leaves like scallions, the larger of the bulbs like shallots, and the solid scapes that emerge from the bulbils like onion-flavored asparagus before they grow bigger and toughen into hollow stems.

Some annual vegetables also behave like perennials by self-seeding if allowed to go to seed, such as arugula, lettuce, kale, carrots (in their second year), spinach, mustard greens, Swiss chards, and other members of the cabbage family. After I’ve harvested all I can use from my Chinese cabbages, broccoli, cauliflowers, and others of the cabbage family in the fall, instead of pulling them out by the root, I cut the plants down to a few inches above the ground, leaving a couple of nodes exposed. Should we have a mild winter that year, most of them would survive and produce an early crop of greens the next spring, with even some early flowers for the bees!

Another common perennial vegetable is artichoke. I’ve grown some with mild success, mostly for its beautiful, purple flowers. Another one is its close cousins, cardoon, which is used in Italian cooking. Unlike artichokes, cardoons are grown not for their flowers but for their long stems, which look like celery. The stems are wrapped in brown paper a week or so before harvesting so that they stay pale and tender. The entire plant is then cut down, the spiky leaves removed, and the stalks sold in supermarkets. 

There are a few perennial vegetables that grow in ponds, watercress being one of my favorites. Not only are they able to withstand a mild winter, they readily self-seed. Since pond water may be contaminated with salmonella bacteria, I wash the watercress carefully and only use them fully cooked in soups and stir-fried dishes rather than raw in salads.

Given all these choices of perennial (and self-seeding annual) vegetables, what would you grow next year?

Asparagus in KokHeong McNaughton’s garden. Courtesy photo