When you look around garden centers, there are lots of herbs for sale. I think people have started to understand the difference that fresh herbs can make in your cooking.
When I look at the herbs available as plants, most of them make sense to me. Perennial herbs like rosemary, thyme, oregano and tarragon grow slowly from small seeds so garden size plants make growing these a lot easier.
I also understand parsley plants. This biennial can be a little tricky to germinate and you have to start the plants very early to have garden-sized plants in the spring. I’m not quite as convinced about basil plants because this annual herb is so easy to grow from seed. But if you’re not looking to load your freezer with pesto and only want one or two plants, I can understand buying them.
But there’s one herb in pots at every garden center that makes me shake my head when I see it – cilantro. If you buy a cilantro plant, I can guarantee that it’ll be dead within a few months. It inevitable demise has nothing to do with the quality of the plant or your gardening skills. Cilantro dies because cilantro is a short-lived annual herb.
A cilantro plant looks a lot like parsley. Both of these herbs grow in a rosette and have a single growing point of undifferentiated tissue (meristem) right around ground level. Before they go into reproductive mode, the meristem of these two plant keeps producing more and more leaves.
A parsley plant keeps producing new leaves all season long. Parsley does this because it’s a biennial – this means that the plant’s first year of life is vegetative and it won’t start to reproduce until the second year. Since almost all gardeners pull up their parsley after one year, they never see the transition from leaves to flowers and seeds.
But they see it when they grow cilantro! While the growth habit of these two herbs is similar, there’s on big difference – cilantro is a cool season annual. An annual is a plant that completes its life cycle within one growing season. In the case of cilantro, it completes that cycle in a few months.
The cilantro plant that you buy is in vegetative mode and it will produce leaves for a while. But once the weather warms and the days get longer, the chemistry of the plant changes and that single growing point of meristematic tissue that’s been producing leaves changes and begins to grow a flower stalk instead of leaves. This change from vegetative to reproductive growth is called “bolting.”
Once cilantro has decided that it’s time to flower, you can’t stop it. The single growing point of the plant has changed and it won’t produce any more leaves. You can cut it back, you can fertilize it, you can do anything you want to renew the plant and it won’t help. Once cilantro bolts, there are two things you can do: throw it out or let the seeds develop and harvest your own coriander!
While cilantro is a short-lived herb, the good news is that it’s really easy to grow from seed. If you sprinkle a few seeds in a pot or in the garden, they’ll germinate easily. The best times to grow cilantro is in the spring and fall because it prefers cool temperatures. If you must have cilantro all season long, you could try growing it inside during the heat of summer on a sunny windowsill or under lights. Or you could freeze some cilantro pesto to add to salsa when it’s too hot to grow fresh cilantro.
There are so many herbs from which to choose. While most are perennial, biennial or long-lived annuals, cilantro is the only one I can think of that’s a short-lived, cool season annual. So if that cilantro plant the you bought dies in a month or two, remember, it’s not you, it’s the plant! And next year, skip the expense of a plant that’ll be long gone before July is over. Instead, buy a packet of seeds and grow your own cilantro in the spring and fall.