The Flowers That Bloom on My Onions

The vegetable crops we grow have specific parts that are edible. For example, we grow tomato, cucumber, eggplant, etc. for their fruit. For these plants to produce fruits, they have to produce flowers. Those flowers must then be pollinated. Pollination brings together two sets of chromosomes, which results in viable seeds which can be planted next year to continue the species. Pollination also causes the ovaries which contain these seeds to swell in size. These swollen make up the fruits – the tomatoes, cucumbers, eggplant, etc. – that we consume as fruits and vegetables.

Meanwhile, we grow other vegetable crops not for their fruits, but for other edible plant parts. Onions, for example, are grown for their fleshy bulbs (which are actually modified leaf tissue). We grow carrots and parsnips for their roots, and we grow greens such as lettuce, spinach, kale, etc. for their leaves. We do not want flowers on these plants. If one of these plants produces a flower, the edible quality of those plants is reduced, since the plant will then put all of its energy into the flower and less into the leaves, stems, and other edible parts.

Under certain conditions, plants such as onions, carrots and greens will produce a flower. This can arise due to cold temperatures (onions) or hot temperatures (lettuce, spinach, and other greens). The unwanted production of a flower is known as bolting.


So how do we prevent bolting? For greens, bolting can be prevented by planting and harvesting them during the cool weather seasons. Lettuce and spinach grown in hot weather have a greater chance of bolting than does spring or fall-planted spinach.

Onion flowering can occur at low temperatures, a process called vernalization. This can happen when planting onion sets that have been stored at temperatures of 40-50oF for two or more weeks are planted right away. To prevent vernalization, expose them to 80oF temperatures for 2-3 weeks, or make sure to plant them early in the spring. To further reduce the chances of growing flowers instead of bulbs, plant onion sets that are half an inch in diameter. These smaller sized sets lack the necessary food reserves for flower production. Larger sized sets have a greater quantity of stored food and are more subject to vernalization. These, however, can be grown for green onions.

Carrots are biennials. They will produce stem, leaves and taproot the first year. If left in the ground over the winter, the following spring, they will produce a flower similar to that of a Queen Anne’s lace. Usually we never see flowers on our carrots because we harvest the roots the first year. However, if you leave carrots in the ground to overwinter, make sure you dig them up before they start to sprout, otherwise, if allowed to flower, the roots will not taste good.


Flowers are beautiful and necessary, but only on certain garden plants. If you want your greens, bulbs, and root crops to be tasty, then don’t let them flower.


Variety is the Spice of Your Garden


On many occasions, when people talk to me about their gardens, they will often ask me about why a certain vegetable crop they planted failed to perform as expected. Perhaps their tomato plants produced little or no fruit, or their cucumbers had a white powdery growth, or their beans failed to grow at all. When I’m asked why they didn’t do well or what they did wrong, I’ll often ask them what cultivar or variety they planted. And nine times out of ten, the answer I get is some variation of, “Oh I don’t know what variety they were; they were just tomato plants I bought at Wal-Mart.” And therein lies the problem, or at least a good portion of the problem.

Allow me to ask a question. When you need to purchase personal transportation, do you go out and buy “a car?” When you need a reliable communication device, do you purchase “a cell phone?” When you need a machine to automatically clean your dishes, do you buy “a dishwasher?” The answer to all three questions is no. You don’t buy a car; you buy a Ford or a Toyota. You don’t buy a cell phone; you purchase an iPhone or an Android. And you don’t shell out your hard earned money for a dishwasher; you buy a Maytag or a Whirlpool. And furthermore, you carefully research your purchases before you dole out your dollars to make sure you are getting something that has all the features you need with a quality that will last at a price you can afford. And why? So that you can be assured that you can drive safely, communicate effectively, and get your dishes sparkling clean. Now if you’re going to go through all this trouble with machines, wouldn’t you want to put at least this much effort into the food you grow and eat?

Tomatoes, cucumbers, beans and other garden vegetables all have what are known as cultivars. These are different genetic versions of the same plant. These different genetic variations result in different colors, shapes, sizes, hardiness, flavor, and disease resistance within the same type of plant.

For example, a Sweet 100 is a small cherry tomato, while a Big Zac is large, meaty Beefsteak tomato. A Thumbelina is a small, round, yellow carrot, while a Purple Dragon is a large, long, purple carrot. A Thumbelina and a Purple Dragon are both a carrot, yet they’re quite different from one another.


So why does this matter? Because just as you want to choose a brand of car that’s suits your lifestyle and driving habits and preferences, you want to choose cultivars of garden vegetables that will have the color and flavor that best delights your eye and tickles your taste buds, resistance to specific diseases (if you’ve had past problems with those diseases), and overall, the greatest chance of success in your garden.

Have your tomatoes produced poorly due to late blight? Then you’ll want to plant a cultivar such as Defiant, which is specifically bred to resist late blight. Do you want to grow a drought-resistant flour corn? Hopi Blue will meet your needs. Do you have hard blocky soil? Planting a standard carrot will result in forked, misshapen roots. Thumbelina carrots produce small, orange, almost round roots that are perfect for firmer soils.

The point of all of this is that if you want a garden that yields large amounts of tasty, mouth-watering vegetables, you’ll have to do a little more than throw some seeds into the dirt, water them, and hope for the best. You’ve got to put as much thought and care into buying your seeds and plants as you would into buying a car or a dishwasher. You’ve got to decide what vegetables you want to plant and then find the cultivars of those vegetables that have the traits that will best meet your wants and needs.

Doing this will most definitely improve your odds of having a successful, high-yielding garden.