Are your cauliflower heads shrunken or floppy? Or have they failed to develop at all? Perhaps they’re discolored or developing in ways you’ve never seen before.
Although the number of cauliflower head disorders listed here may seem daunting, please don’t let them stop you from growing this lovely vegetable! You may never encounter any of these problems. Consider this list an info sheet of what might occur so you can be prepared.
Below are 12 of the most common cauliflower head disorders, as well as what causes them and how to sort them out if they appear.
Cauliflower Head Disorders
1. Failure to Develop Heads (aka Blind Bud or Bud Blindness)
It’s immensely frustrating when you put a ton of time and effort into growing cauliflower, only for them to develop abundant foliage but no heads.
There are a number of cauliflower head disorders that may prevent them from developing the way they should, but failure to flower (“bud blindness”) often comes down to the following issues:
- The wrong seeds for your climate
- Inappropriate soil makeup
- Insufficient light
- Too much heat
Check seed packets carefully to ensure that the cultivar you’re eyeing will thrive in your USDA Growing Zone. A type that thrives well in Wisconsin is going to die in Arizona.
Similarly, ensure that your soil is right for this plant: cauliflower is a heavy feeder, so the soil will need to be amended with plenty of aged manure or compost.
Additionally, if your soil has too much nitrogen and insufficient potassium or phosphorous, you’ll get leafy cauliflower with no heads.
Finally, cauliflower can be extremely finicky about its light and heat needs. Like most other brassicas, it does require a fair bit of light to thrive, with at least six hours of direct sunlight daily, but it’ll bolt in hot weather.
As such, unless you live in a cooler climate, aim to grow yours in the autumn or start them indoors in the early spring rather than growing them at the height of summer.
Learn more about growing cauliflower in our complete growing guide.
2. Loose Curd
If your cauliflower heads look like mounds of loose cottage cheese instead of tightly packed, dense florets, you likely have a watering problem. This is one of the easier cauliflower head disorders to sort out, but it’s helpful if you plan well ahead of time, too.
Cauliflower plants hate wet feed. If the soil they’re planted in isn’t draining properly, they’ll be stressed out.
In contrast, they’re also heavy drinkers: if you haven’t been consistently watering them, that will also stress them out and cause the florets to loosen and pull away from each other.
Make sure that the soil you’re planting them into is nutrient-rich and well-draining, and then water your plants consistently at the soil level. Watering from above can cause mildew issues, so your best bet is a perforated soaker hose set on the soil.
Either set up a timer so your plants will get watered whether you’re home or not or set timer notifications on your phone to remind you.
3. Loose Curd with a Yellow Hue
Now, if your plants’ heads have loose curd and a yellowish tinge to them, they’re getting too much sun. This often happens in hotter environments or if cauliflower is being grown at the height of summer.
Essentially, the hot midday sun is scorching your plants, making them swoon and wilt.
Of all the cauliflower head disorders on this list, this one is the easiest to fix. Simply pull some of the leaves over the head into an umbrella shape and tie them securely in place.
The head will continue to develop within the shade of this lovely leaf canopy and won’t get sunburned.
4. Loose Curd and Stunted Growth
These plants can be rather delicate and precious when it comes to temperature fluctuations. They’re sensitive to both heat and cold and may end up with stunted growth if they aren’t hardened gently over time.
If you’re starting cauliflower from seed, you’ll need to start them indoors and then harden the seedlings softly over the course of several weeks before planting them out in your garden.
One of the easiest ways to avoid this issue is to buy more mature seedlings from a local nursery. They will have gone through all the hard work of babying these plants, so you don’t have to. You can simply pick up a couple of plug packs and pop them into your garden after the last frost date.
5. “Buttoning” Cauliflower Head Disorders
Do your cauliflower florets look more like Queen Anne’s lace (Anthriscus sylvestris)? This is known as “buttoning,” which results in teensy florets forming on long stalks. It’s among the cauliflower head disorders on this list that can have a few different causes, so let’s take a look at the possibilities:
Insufficient nitrogen
Too much nitrogen can shrunken cauliflower heads, so test your soil to see what the levels are like. For healthy cauliflower plants, the nitrogen level should be between 40 and 60 ppm.
Seedlings Planted Too Late
If you start your seeds indoors, you’ll have to harden them off gradually before planting them out in the garden. That said, if you wait too long, the seedlings will miss their optimal development window and end up stunted, creating buttoned heads.
Inconsistent watering
Since cauliflower plants are heavy drinkers, they need a consistent watering pattern to stay healthy. Periods of drought followed by intense soaking can stress out the plants, causing them to button. To avoid this issue, water regularly for consistently moist soil.
Whatever the cause, the result of buttoned cauliflower will be stunted, awful-tasting florets.
At this point, either use the plants as pig fodder or compost them, as they’re unfit for human consumption. In fact, when cauliflower head disorders do appear, it’s best to find alternate uses for the plants rather than attempting to eat them.
Read our article for additional tips on using table and garden scraps to feed pigs.
6. Brown Curd
This sounds like a country song title, but it’s one of the more frustrating cauliflower head disorders. Those of us who love the creamy white heads that these plants create are often heartbroken to see them looking unfit for anything but the compost heap.
In addition to being discolored, the heads will also be stunted in growth and have a notably bitter flavor.
Brown cauliflower curd often occurs when the soil has a boron deficiency. If the soil on your property is more alkaline than acidic, test the soil. If the boron levels are just fine, then check your plants carefully for aphids.
The honeydew they leave in their wake can act like glue for dirt and dust particles, making the heads look brown and unhealthy.
7. Purple-Tinged Curd
If you’ve planted a white cauliflower variety, you may be concerned if the florets seem to take on a mauve or purple hue. This is one of those cauliflower head disorders that can be caused by too much sun exposure.
As mentioned, cauliflower is extremely sensitive to heat and light fluctuations, and it often gets stressed out or scorched by too much direct sunlight.
Simply rig up shade to shield them from midday sun and ensure that they have enough mulch around them to keep their roots cool and moist. This should stop the purpling and prevent any more from forming.
8. Open Curd with Leaves and Flowers Poking Through
An ideal cauliflower head will be a tightly packed curd of deliciousness. As such, it can be rather distressing to see leaves poking through separated curd bits.
This is one of the cauliflower head disorders that’s similar to “buttonin.” When this happens, the curds start to pull apart, allowing foliage to grow up and through the heads.
This often occurs during periods of inconsistent temperatures but may also occur if your cauliflower plants are stressed out from overcrowding.
Ensure that there’s plenty of room for your plants to stretch out so they aren’t competing with their neighbors for nutrients or water. It’s better to harvest cauliflower heads when they’re just about at their prime rather than leaving them to over-mature on the stalk.
If you’re interested in discovering the best companion plants for cauliflower, learn more in our guide.
9. A Tall Stalk with Flowers On Top
If your cauliflower plant has mysteriously transformed into a tall, flowering stalk, then congratulations: your plant has bolted. This often occurs in hot weather, which tells the cauliflower that it has to go to seed as quickly as possible in order to ensure its procreation.
As such, it bypasses the head-forming stage and forms flowers and seeds rather than a nice, round globe head.
This generally happens if there are drastic temperature fluctuations in your region, as cauliflower is sensitive to both heat and cold. If there’s a sudden cold snap or heat wave, the plants will panic and go to seed.
As far as cauliflower head disorders go, it’s one that we have little control over.
You can try to mitigate the temperature damage by taking precautions to protect your plants from inclement weather, but no matter how vigilant you are, Mother Nature has the final say.
Keep frost cloth handy to protect your plants during cold spells, and keep both shade fabric and mulch handy to protect them from hot summer temperatures.
10. Split Heads
Unlike loose curd, head splitting looks more like someone has taken a knife to your cauliflower’s heads and pried them apart. This usually happens late in their growing cycle, just before you harvest them. Of course.
Head splitting often occurs when there’s a period of heavy rain at the end of their growing season. The sudden **whoosh** of excess water can cause them to uptake too much moisture and literally burst at the seams.
As such, keep an eye on the weather as harvest season approaches—that way, you can harvest them early and prevent them from splitting apart.
11. Ricing
Do the individual florets on your cauliflower heads look elongated and grainy, kind of like bunches of rice mashed together? This is known as “ricing”, and is most often caused by intense temperature fluctuations.
Avoid this issue by choosing ricing-resistant varieties, particularly those that are ideal for your growing zone. Then ensure that you have a means of shielding them from both intense sun and unexpected cold snaps.
12. Watery, Slimy Curd
If you go to pick your cauliflower heads and discover that the curd feels waterlogged and slimy, you’re likely dealing with bacterial soft rot. It’s caused by bacteria in the Erwinia and Pectobacterium genera and results in wet, squishy, foul-smelling heads.
There is no salvaging plants affected by this type of bacterial issue, so you’ll need to burn them in order to prevent the bacteria from contaminating your compost bin.
Soft rot is caused by wounds in the plant’s stem, allowing the bacteria to get into the head from the inside. As such, it isn’t immediately apparent as it’s forming, and is often only discovered after the head has been harvested.
Avoid this issue by protecting plants against insect, animal, or manual damage, and by ensuring that the soil is well draining.
You can get some cultivars that are resistant to bacterial soft rot, but be aware that no varieties are completely immune. If and when you discover this issue, destroy any affected plants, solarize the soil, and don’t plant any brassicas there for at least three years.