Stage #1: The Cotyledon Stage
These tiny "pre-leaves" appear on the infant plant before the "true leaves" do. The cotyledon leaves do not resemble the true leaves to follow in look or in taste. Maybe there'll be a thrill-seeking market for them someday—but they are so tiny that most farmers today just let 'em keep growing. The Chef's Garden, by the way, is an exception. They harvest them for one chef only: Tom Keller of the French Laundry in Napa Valley, who's very fond of "pushing the envelope." Accordingly, at The Chef's Garden they often refer to the cotyledon stage as "the Keller Stage" ... or "TK" for short.

Stage #2: The Micro Stage
This is the first really commercially viable stage—and, accordingly, the phrase "micro-greens" has slipped into our epicurean vocabulary. Micro-greens are the plant's first true leaves, replacing the cotyledon leaves. They are usually harvested with stalk or stem attached—making the unit of thin stem and just a few micro-leaves look like a sprout. These tiny, tiny leaves have exactly the same look and shape as the mature leaves that they will grow up to be if left alone. Sometimes, they are thrillingly intense in flavor. They are also phenomenally expensive; if mature leaves are $2 a pound, these may cost $32 a pound or more.

Stage #3: The Petite Stage
When the plant begins to form not just individual leaves, but clusters of leaves, the greens are called "petite." This stage is very popular at The Chef's Garden; Lee Jones says that chefs like it because it's when they can first say "this really is cilantro!"

Stage #4: The Ultra Stage
When the growing plant reaches 2-3 inches, Lee Jones calls that the Ultra Stage. The Chef's Garden is very precise about an in-between stage like this, because they want their customer-chefs to have the option of buying greens at precisely the desired size and structure. By the way, up to this stage, all harvests from the various plants are principally leaves.

Stage #5: The Baby Stage
This is a crucial stage ... and one that's very important in the marketplace. When a plant first develops a head, or a root—the thing we always think about eating, like the stalks of bok choy, or the beet itself in a beet plant—it has reached the Baby Stage. The heads and roots are very fashionable—baby carrots, baby bok choy, baby zucchini, etc. —but, in some plants, the baby leaves that grow out of the baby heads or roots are also fantastic (like baby beet greens.) The Chef's Garden and many farmers' markets make baby greens available, and baby greens are the absolute height of fashion today.

Stage #6: The Young Stage
There is no essential botanical difference here from the last stage—but when a plant matures to become a little bit bigger than it is in the Baby Stage, it has reached the Young Stage. Often, it's a close call; farmers may call something a Baby plant (because the name has such cachet), when in fact it may be a little older than that (which means to the farmer that the crop is a little bigger). When it comes to greens—as we reach the Young Stage, we start getting into the realm of leaves that are bigger and, usually tougher.

For some plants, like some lettuces, this is not a problem when you're wanting to make a salad; but for some plants (like kale) moving through this stage means that the leaves are becoming less and less desirable for salad.

Stage #7: The Commercial Stage
In this stage, the plant has reached full vigor, its commercial maturity—but has not yet begun to grow the elements that will result in reproduction. For the heads and roots—as in broccoli, carrots, turnips, parsnips, radishes, squash, etc. —the commercial stage is the biggie, the one that most often comes to market. For conventional greens and lettuces, it is also the biggie: the icebergs, romaines, green-leaf lettuces, Boston lettuces, etc. that you see in the supermarket are all at the Commercial Stage. But designer-green freaks feel that even these lettuces are better, sweeter, more intense-tasting, better-textured at younger stages. And farmer certainly know that when some greens reach this stage—beet greens, dandelion greens, mustard greens, kale—they become much less attractive for the salad bowl. For specialist growers of designer greens, the commerial stage is best left to the farmers who grow greens for supermarkets.

Stage #8: The Flowering Stage
This occurs when the plant begins its reproductive cycle, starting to bud and bloom. The plant itself at this stage, and its leaves, can sometimes be intensely flavored--but not always. The flowers (or blooms, or blossoms) themselves are sometimes of gastronomic interest. There has been a boom in the use of zucchini flowers in recent years, of course--but other flowers can be even more interesting in flavor (see notes below on arugula flowers and pea flowers.)

Stage #9: The Seed Stage
At this stage, the plant has come to full maturity. It now yields seed stalks, or pods, that will someday yield the next generation—unless the farmer grabs them. According to Lee Jones, these seed stalks or pods have some of the most intense flavors of any stage in the cycle—but are also hideously expensive. He's especially fond of the seed stalks and pods that are yielded by bok choy, tatsoi, and mizuna. You don't have to worry much about these: you probably won't see them at farmers' markets.

For more of David's information on microgreens and his newsletter The Rosengarten Report, go to Davidrosengarten.com.

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