How To Keep Cauliflower White While Growing

Cauliflower is a great vegetable to grow in your garden. It’s easy to maintain, can be eaten raw or cooked, and it’s healthy. Cauliflower that grows in your garden will be white. Still, the color can change when you harvest it later, which may be unideal for some backyard farmers.

To keep your cauliflower white while growing it, you can tie the leaves of your cauliflower plant around the head in a process called blanching. Additionally, paying attention to the health of your cauliflower can help keep them nice and bright white.

This article will explain how cauliflower becomes brown and how to prevent this from happening so you can enjoy eating all of your homegrown vegetables! Additionally, we’ll discuss the ideal conditions for your cauliflower.

Ways To Keep Your Cauliflower White

To keep your cauliflower white, you should incorporate a combination of the following strategies into your gardening routine:

  1. Blanching your cauliflower.
  2. Watching your cauliflower’s health.
  3. Being cautious of molding and diseases.
  4. Planting the right variety.
  5. Be intentional about location.
  6. Harvesting and storing properly.

Observe your cauliflower plant beforehand to do a basic investigation. What is causing the discoloration? Is it molding, disease, sunlight, or illness? Though all of the above can be incorporated into your gardening routine, a quick fix requires knowing what’s happening.

I’d highly suggest using a moisture meter or any other tools you have at your disposal to check your plant’s health before proceeding with just one of the following strategies. However, if you’re game to add all of these to your routine, your cauliflower will thank you for it!

1. Blanch Your Cauliflower

Cauliflower heads are made up mostly of water—about 95% water by weight! This means they contain a lot of nutrients and sugars that need to be protected from oxygen and light exposure while developing. 

Suppose you leave your cauliflower out in the sunlight too long. In that case, those nutrients will oxidize, turning them brown and reducing their shelf life significantly. Therefore, you need to employ some steps to protect the plant from the intense heat and light from the sun.

Cauliflower plants love their leafy protection, which helps them stay white through harvest. However, wind and other factors may blow away their natural covering. In such cases, your cauliflower needs human intervention.

Blanching is the process of covering a plant with leaves to protect it from sunlight. You can blanch your cauliflower by covering it with its own leaves or placing a cloth over the top of the plant. Some farmers are known for tying their leaves with little rubberbands, which can damage the leaves, but will help protect your cauliflower!

Products for Blanching and Sun Cover

Rubber bands from your junk drawer or even from your beauty-supply kit will work to blanch your cauliflower. If you plan on going this route, I’d suggest getting something non-fussy and not too small. A scrunchie won’t work, nor will the tiny rubber bands meant for children’s hair.

You can go with something like the JIKIOU 750Pcs Rubber Bands (available on Amazon.com), which is affordable and not too small for your cauliflower leaves. An extra small rubber band risks cutting off the leaves entirely or not even wrapping around the leaves. The JIKIOU brand would be a perfect size.

With a little extra money to spend, you can invest in a garden shade cloth that covers your entire crop or a greenhouse.

2. Watch Your Cauliflower’s Health

Keeping your cauliflower white while growing is a matter of providing it with the right nutrients and having it in the best environment possible. Depending on your area, you may need to make adjustments to accommodate the growing cauliflower. 

Cauliflower can grow optimally and remain white if you meet the following essential needs:

Ideal Cauliflower Soil pH

The pH of your soil is important because it affects the availability of key nutrients and helps protect plants against pathogens such as fungi, bacteria, and viruses.

Cauliflower thrives in slightly acidic soils with a pH between 6.0 and 6.8. If you have alkaline soil (pH above 7.0), you can adjust this by adding sulfur according to your soil test results. The pH can also be reduced by adding compost.

You can also adjust the pH through watering. If your cauliflower is not growing well due to high levels of magnesium, potassium, or calcium in the soil, adding peat moss or vermiculite into your mix will help keep those elements from building up in the plant tissue.

However, adding amendments to change the soil pH is not an instant remedy, and the pH of garden soil will go back to its natural level over time. Test your soil to confirm if it’s suitable for growing cauliflower. If it’s too alkaline, you can find a different area to grow cauliflower.

Fertilizer and Nutrients

A high-nitrogen fertilizer will increase nutrient availability for all vegetables. However, it needs to be applied at lower rates than nitrogen fertilizers for other vegetables. Check the nutrient availability in your soil and when necessary, apply a half-strength fertilizer rich in nitrogen with low levels of potassium and phosphorus.

Ideal Watering Conditions for Cauliflower

While cauliflower isn’t a particularly thirsty plant, it does require regular watering to help keep it healthy. That being said, you’ll want to avoid overwatering. If you do this on purpose or accidentally (we’ve all been there), your cauliflower will start growing mold and might end up stunted

A cauliflower plant is extremely susceptible to mold by nature. You can’t really do much about genetics. Still, you can feed your cauliflower a high-nitrogen fertilizer and water it properly so that it doesn’t get moldy.

Regularly checking the soil with your finger is a good way to make sure that your plants have enough water without being too wet or too dry. Alternatively, you can use a reliable moisture meter to ensure you are feeding the plant the proper amount of water.

Sunlight Conditions for Cauliflower

In general, a cauliflower plant needs plenty of sunlight, so plant your cauliflower in full sun if possible. Cool-weather crops like broccoli and cauliflower love a nice, sunny spot to grow tall and strong. 

However, suppose there aren’t enough hours of sunlight for these plants to thrive during their growing period (about six months). In that case, they will start turning yellow instead of white—and it’s very hard for us humans not to notice when something looks yellower than it should be!

Planning the location of your cauliflower before planting can go a long way to keeping them healthy and white. Ideally, they should receive bright morning sun but get some shade from the afternoon sun to protect them from discoloration.

3. Be Cautious of Cauliflower Molds and Diseases

Another reason for the discoloration of the cauliflower plant is that it may have become moldy due to overwatering. A head of cauliflower has so many nooks and crannies that water can get into. If they don’t dry in the sun, your cauliflower becomes susceptible to mold growth. It helps to be cautious of the molding in the cauliflower.

You must ensure you don’t let your cauliflower get too much water. Otherwise, it will mold easily because the water gets between all the flowers. If you tend to water at night, your cauliflower won’t have proper time to dry, so it’ll likely get moldy.

Additionally, you should be on the lookout for a few cauliflower pests and diseases. Remember, there’s a big difference between discolored, not-mature, or browning cauliflower and diseased cauliflower.

I’ll dive into common diseases a little more below.

Common Cauliflower Diseases

Here’s a look at the most common cauliflower diseases, what they look like, what may have caused them, and how to avoid them:

  • Cauliflower mosaic virus (CMV). This viral disease causes small yellow spots on leaves that eventually merge to create large areas of discoloration. Leaves may also show mosaic patterns or mottling. Plants infected with CMV may also produce stunted heads or no heads at all. CMV is spread by aphids, so controlling these insects will help prevent this disease from spreading through your crop.
  • Downy mildew. It causes fuzzy white patches on leaf undersides. It can result in premature defoliation if not controlled early in the growing season. This fungal disease thrives in cold weather conditions, so starting plants indoors when temperatures are high will help prevent downy mildew from affecting your cauliflower plants later in the year when temperatures drop outside again after summer has ended.
  • Black Rot. Black rot is a fungal disease that causes dark brown spots on leaves. The spots may spread to the stem and flowers, killing them prematurely. Leaves may turn yellow and die back if black rot is severe enough.

This video shows an example of what a cauliflower might look like if it had black rot:

Check for other common diseases if you’ve noticed that your cauliflower looks beyond discoloration and might actually be sickly rather than discolored.

4. Plant the Right Variety of Cauliflower

If you’ve tried everything and the cauliflower just isn’t as white as you expect it to be, it may be because it’s not supposed to be. You’d be surprised how many gardeners wait patiently for their cauliflower to turn white just to realize they planted a different kind than the store-bought cauliflower they’re used to!

If you’ve found your cauliflower is green or isn’t changing to white no matter what you do, make sure you’ve planted the right variety. There are dozens of varieties of cauliflower, and even more close relatives of the plant, so it’s possible you’ve planted the wrong kind. Keep all of this in mind as you proceed with the following tips!

Cauliflower is available in green, purple, and orange varieties. They each have different flavors and growth patterns and appear different as they grow. Most farmers will grow one of the following:

  • Snowball Cauliflower – this variety has a white head with green leaves. It’s popular because it’s so easy to grow and tastes great.
  • Romanesco Cauliflower – this is an Italian heirloom variety with a unique appearance with spiraled heads that resemble Romanesco broccoli but with a much milder flavor than broccoli.

The white variety is most popular, but the other colors are becoming more common in gardens and farmers’ markets. The orange variety is especially beautiful when cooked because it turns a bright yellow color and has an interesting flavor profile that is different from other types of cauliflower. Purple cauliflower is also gaining popularity because it looks so pretty on a plate!

So if you’ve found that nothing will turn your cauliflower white–because it’s currently purple, orange, or green–it may be the species. Don’t be embarrassed, as it happens to the best of us!

5. Be Intentional Where You Plant Your Cauliflower

If you want to grow white cauliflower in your garden, the soil type, quality, space, and location matter. Even the companion plants can affect how easily–or hard–you can keep your cauliflower white while growing.

Cauliflower Plants Need Plenty of Space

It’s important to space out your cauliflower plants so they have plenty of room to grow. Cauliflower has a large root system and takes up a lot of soil. So if you want to grow them in containers, make sure to plant them in pots with plenty of room at the bottom for their roots.

Companion Plants for Cauliflower

Cauliflower plants have varieties of other plants they grow well with and some that they don’t grow well with. Some plants grow together symbiotically, while others compete for nutrients. 

Don’t grow your cauliflower in the same bed as the following plants:

  • Leeks. These can cause blights on your cauliflower if planted too close. They may also crowd out your cauliflower by growing tall enough to shade them from sunlight.
  • Tomatoes. Tomatoes need lots of nutrients to grow. They also grow relatively quickly, so they may take some nutrients from your cauliflowers.
  • Melons. Melon plants can compete for sunlight with cauliflower.

You don’t need to grow your cauliflower all alone, though. Ideal complimentary plants for your cauliflower plant include:

  • Onion and garlic. Some gardeners swear this will deter any pests, which will help if you’re worried about mosaic or blight.
  • Sage. Sage does well in most gardens because it helps attract pollinators.
  • Cucumbers. These plants can provide natural shade to your cauliflower if they’ve been getting burnt up by the sun.

6. Harvest and Store Your Cauliflower Properly

If you want to keep your cauliflower white, you first must harvest it at the proper time. A  cauliflower plant usually needs around fifty days to grow before harvest. If you harvest too early, or if there are still green leaves on the head, they’ll likely turn brown as they dry.

Once your cauliflower is harvested and ready for eating, you’ll want to carve it into smaller pieces as soon as possible. This step will be quick and easy if a food saver or vacuum sealer is available at home. But if not, carving the cauliflower into smaller pieces using a sharp knife should do the trick just fine.

Don’t forget to completely dry your cauliflower after cleaning it. As mentioned above, cauliflower is particularly susceptible to molding, so drying it completely lessens the chances of any mold issues.

Once the cauliflower is ready for eating—that is, once there’s no longer any hint of green left on its surface—you must store it properly so that all those lovely white florets aren’t ruined by exposure to other chemicals or sunlight (which causes oxidation).

To ensure that the cauliflowers stay fresh and white for their entire shelf life (about 3-5 days in the fridge), vacuum seal each piece of cauliflower separately before freezing them in an airtight container in your freezer.

Is Discolored Cauliflower Safe To Eat?

So, in the meantime, what should you do with your discolored cauliflower?

Cauliflower is typically okay to eat even if it’s discolored, as long as it’s not moldy or largely off in color. You should toss it if you notice black, brown, or blue. However, it’s usually safe to eat if it’s slightly browned or a little yellow.

Always be vigilant about plant disease and mold. This can happen naturally as the plant grows and matures (even before you harvest it!). However, if the cauliflower head has turned brown due to sunlight or heat exposure, there is no need to worry.

Of course, if you’re like me and want the cauliflower to be as white as possible when you serve it, you’ll want to know how to keep it that way. Following the above tips for harvesting and storage should help with that. However, if it’s too late, just scan for any mold or pests before serving. Your cauliflower should be safe to eat otherwise.

Additionally, if they’re discolored because you’ve harvested them too early, they may still be safe to eat. Just know that a too-early harvest can’t be saved with storage techniques.

Conclusion

To keep your cauliflower white while planting, you can utilize farming strategies such as blanching or soil testing. Make adjustments if needed when it comes to watering, sunlight, and pH. With all of these tips, your cauliflower should be white at harvest and stay that way once properly stored.

Suppose you can’t seem to get your cauliflower to grow white no matter what you do. In that case, you should check to ensure your seed packets were for the variety you intended. There are dozens of species of cauliflower, and you may find you have planted the wrong one!

Alexander Picot

Alexander Picot is the principal creator of TheGrowingLeaf.com, a website dedicated to gardening tips. Inspired by his mother’s love of gardening, Alex has a passion for taking care of plants and turning backyards into feel-good places and loves to share his experience with the rest of the world.

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