Understanding the life span of your crops is key to a vegetable garden

WHEN YOU’RE THINKING about planting anything, there are a few basic questions you always should ask. Of course you’ll want to know how much sunlight the plant needs, what kind of soil it prefers and how big it’ll grow.

You’ll also want to know how long you should expect it to live. When it comes to life expectancy, plants usually are categorized as annuals, biennials or perennials. Annuals are expected to live for a single year; biennials live for two years; and perennials can live anywhere from three to 3,000 years, give or take.

In most cases, this is all the info you need. However, like most things, it gets a bit more complicated when you start talking about food crops. Once you get into the vegetable garden, it’s essential to understand that there’s a meaningful difference between the concept of an annual plant and that of an annual crop.

An annual plant is expected to germinate, grow, flower, set seed and die all within a single year. However, an annual crop is any plant that’s replanted every year, or even several times within a single year. Thus, annual, biennial and perennial plants all can be grown as annual crops.

A good example of a biennial plant grown as an annual crop is the carrot. Because a carrot is harvested for its root, and that root develops during the first growing season, most carrots are harvested in the same year they’re planted. If you want to collect carrot seed, you need to leave some plants in the garden for two seasons, because they’ll flower and set seed during the second summer.

Even perennial plants are grown this way. Tomatoes are perennials in tropical areas where it doesn’t frost. However, because they’re very intolerant of cold weather, we have to grow them as annuals. Thank goodness they grow so quickly.

Biennials and perennials can be ready to harvest only a few weeks or months after they’re planted. Even though cabbage is a biennial plant, you easily can plant and harvest it three or four times during a single growing season. 

I find crop life span to be one of the most helpful concepts when planning, planting and managing the vegetable garden. It’s extremely useful to know how long a plant will be in the garden, so you can replace it with another crop as soon as it’s finished, maximizing your space and increasing your yield.

Here are the categories that I break annual crops into:

● Short-season: These crops might take only a month or six weeks to reach maturity, so they can be planted many times during the season. Most short-season crops are intolerant of high heat and are best grown in spring and fall. Plant them often, small amounts at a time. If you plant too much at once, you might be overloaded one week and then have zilch the following week. Examples include lettuce, arugula, cilantro and radishes.

● Half-season: I generally plant these twice a year. They take two or three months to grow to maturity, so you can plant them in spring and then again in the middle of summer for a fall harvest. I usually plant kale in April and then again in mid-July. Once your spring half-season crops are harvested, replace them with short-season crops or another planting of half-season crops. Examples include broccoli, cabbage, kale, bush beans and summer squash.

● Long-season: These crops are usually planted just once a year. Compared to the crops above, it takes them a relatively long time to grow from seed to harvest. You can start tomatoes from seed indoors in March, transplant them into the garden in May, and harvest them in August and September. That’s about seven months. Plan to keep long-season crops in place through the whole growing season. Examples include tomatoes, winter squash, Brussels sprouts, peppers and eggplant.

As if you can’t tell, I’m getting excited for this coming growing season. I’m still finalizing my annual crop plan, but you can be sure that it won’t be filled with just annual plants.