Cauliflower is one of my favorite vegetables to eat and I wanted to grow some in my container garden. But it’s a somewhat large plant and I had the question of can you grow it in a pot?
You can grow cauliflower in a pot that is 10 to 12 inches deep and wide. Grow them in a cool-season that is suitable for cauliflower such as early spring or late fall. Use good potting soil and add compost or fertilizer every month. Cauliflower grows well with at least 8 hours full sunlight and good watering.
Cauliflower can be one of the suitable plants to grow in a container but it does need a little maintenance. Make sure to read all the steps below that will help you grow them in a pot.
1. Choose the best time to grow cauliflower
Cauliflower is an interesting plant with some distinct needs. It has a reputation for being sensitive and difficult to grow. However, most of the issues that gardeners face with this crop revolve around poor planning.
The crop requires cool temperatures to truly thrive.
You have a couple of options for when to plant cauliflower. Because it does best in cooler weather, you can aim for spring harvest or autumn harvest. It all depends on your growing season.
If you’re looking to enjoy the vegetable in the spring, you must start the seed indoors. Aim to sow the seeds or plant your seedlings about 10 weeks before the last average frost date.
You can use historical data to figure out your timeline. If you don’t have access to past frost dates, you can call your local Extension office. The experts there will give you all the information you need.
Don’t worry too much if things aren’t exact. There’s no way to plan around Mother Nature. The plant will do a lot of its growing indoors, so it shouldn’t be a problem if you’re a few days off.
For fall harvests, you’ll need to look for information about the average first frost date. Once you figure that out, plan to start your cauliflower about 12 weeks before you expect the first frost to come.
2. Figure out how long it will take to grow
Cauliflower doesn’t take as long to grow as most people think. For many gardeners in temperate climates, it will take as little as 60 days.
That said, there’s a lot of fluctuation here. Cauliflower has a wide hardiness range, growing in zones 2 through 11. That’s pretty much all of the United States.
Obviously, not all cauliflower varieties will flourish everywhere. There are 4 major cauliflower varieties and countless unique cultivars. Each one has its own growth cycle.
Plus, you have to factor in your growing method. You can grow cauliflower from seed or young seedlings.
If you go the seed route, you can expect a longer growing time. Generally, it takes between 85 to 130 days from sow to harvest.
But if you use transplants or seedlings, the average growth time is much faster. Seedlings take about 55 to 100 days depending on the cultivar.
Make sure you do some research about the particular variety you’re planting. You may have to adjust your planting time if you’re in for a particularly long growing cycle.
3. Choose the right pot to grow cauliflower
The key to successful cultivation is choosing a suitable pot. Crop vegetables like cauliflower need ample room to grow. While they can flourish just fine in pots, you need one that’s going to accommodate its needs.
Choose a pot that’s roughly 12 to 18 inches in diameter. For depth, aim for a container around 8 to 12 inches tall. That’s suitable for the shallow root system of the plant.
These measurements are the bare minimum for cauliflower. But, you can always go bigger.
In fact, many gardeners choose to use makeshift containers. If you have the room, try using a barrel half or old trash bin. In a larger container, you can easily grow up to 3 plants.
There are no strict requirements when it comes to material or weight. However, you might see more success with a thicker pot made of ceramic or terracotta.
Terracotta, in particular, does a fine job of insulating the soil. Cauliflower can experience problems if the weather warms up too soon. An insulating pot may make it easier to keep soil temperatures at an appropriate level.
4. Prepare the pot to plant cauliflower
There are a few additional steps you need to take before you start planting your cauliflower. The first is to make sure that your pot has adequate drainage.
Cauliflower plants will not tolerate standing water. These plants like moisture. But excess sogginess will quickly cause root rot.
To ensure that this doesn’t happen, drill a few holes in the bottom of the container. Many pots you get at the gardening center already have a few holes in them. But feel free to add some more if you think that the existing holes are too small.
With makeshift containers, drilling new holes is a must. Pop several holes around the perimeter of the pot and near the center.
Preparing the Soil
Next, you must prepare the soil. Cauliflower can grow in any old potting mix. But, it pays to do a bit of amending beforehand.
Plan your growing season early and try to amend the soil several months before you plant. This will give the medium some time to improve.
There are two main goals with soil preparation. You need to enrich it with nutrients and ensure that it’s at the right pH level.
Cauliflower plants prefer soil that’s rich in organic matter. Take some organic compost and work it into the soil. Use a small shovel to work it in and get everything fully incorporated.
Once that’s done, perform a soil test. Ideal pH levels are between 6.0 and 6.8. This slightly acidic range will maximize nutrient availability. A small amount of peat moss will lower the pH balance. But don’t overdo it. You will start to run into problems if the pH level falls below 6.0.
5. Plant cauliflower seeds in the pot
Planting from seed is a great option if you want full control over the type of cauliflower you cultivate. It does take longer to reach harvest. But, the extra time is well worth the wait.
For the best results, you should plant your seeds directly into the pot you intend to grow the plant in. It’s possible to start with seed trays. However, this would require transplantation later on. These plants are already sensitive enough. You don’t need another step to stress the plant out.
Fill your pot to about half an inch from the rim. Then, place 4 seeds in the center of your pot and lightly cover them with soil.
You don’t need to worry about spacing. Using multiple seeds will give you a better chance of germination. However, you will remove 3 of the seeds after they sprout. For now, the goal is to make sure that you have at least one of the seeds sprout.
Water the soil lightly. It needs to be moist but not soggy. Make sure to check the moisture levels daily. Keeping the soil moist is crucial for germination.
Place your pot somewhere warm inside your house. Cauliflower seeds can germinate in temperatures as low as 50 degrees Fahrenheit. However, optimal conditions are around 80 degrees. Put the pot in a warm room or take advantage of a warming pad to keep the soil in good shape.
6. Plant cauliflower seedlings in the pot
If you want to harvest your cauliflower sooner, seedlings are the way to go. They are available at most nurseries and garden centers. Seedlings have already gone through the tough germination phase. They are several weeks old, making them a suitable candidate for transplanting.
Fill your pot with soil and leave about an inch at the top. Use a small shovel or your hands to dig out a hole that’s roughly the same size as the seedling container.
Now, gently squeeze the sides of the plastic container to loosen the soil and seedling. It should slide right out in one place. The soil is still delicate, so be gentle.
Place the seedling and its soil in the new pot and fill the hole. Give the seedling a good watering and put the pot in a warm location inside your home.
For both seeds and seedlings, the plant will stay indoors for several weeks. As it grows, keep the soil moist and make sure temperatures are stable.
7. Provide required sunlight to cauliflower
Cauliflower plants love the sun. But, they can be a bit trickier to manage than other plants because of their strict temperature management. Not only that, but you have to know when to provide sun.
Providing Sun Exposure
You need to provide sunlight as soon as your cauliflower seeds sprout. If you plant from seedlings, you need to put the pot in a sunny spot from the jump.
However, you can’t take them outside just yet. So, prepare to create some room near a window.
The moment you see your seeds sprouting, place the plant in a sunny window. A south-facing window is ideal. It receives exposure throughout the day. Some shade is fine, but you’ll experience better results if you manage to give the cauliflower plant full sun.
You can also use a grow lamp if natural sunlight is unavailable.
Moving the Plant Outdoors
After several weeks of flourishing inside, you can move the plant outdoors to receive unencumbered sun exposure.
If you’re planting for a spring harvest, the best time to move the crop outdoors is about 4 weeks before the last frost. That timeline is a general guide. Cauliflower grows best when daily temperatures are in the 60s. So, check the temperature daily and move your plants outside when the weather is right.
For fall plants, you’ll want to move the pot outside 6 weeks before the first estimated frost date. Again, check to make sure that daily temperatures are in the 60s. Too much heat is just as bad as too much cold.
Put your pots in a spot that gets at least 6 hours of full sun every day. More sun exposure is better. The more sunlight your plant gets, the healthier it will be.
8. Water cauliflower plant in the pot
On average, cauliflower plants need between 1 and 1.5 inches of water every week. In particularly dry regions, you may need to provide upwards of 2 inches a week.
Stick to a regular watering schedule. Cauliflower plants don’t tolerate drought whatsoever. You must keep the soil moist and well-hydrated.
When you water the plant, do so deeply. Let the water seep out from the bottom to ensure that the roots are getting full access to the water.
Try to keep the leaves dry as well. The occasional splash is no big deal. But regular saturation will cause fungal problems. You also want to avoid overwatering and soggy soil. Cauliflower is quick to rot, so you must avoid any major watering discrepancies.
9. Thin unwanted cauliflower seedlings
Remember how I said that spacing for cauliflower seeds wasn’t a big concern? Well, it does become an issue once the seeds start to sprout.
When you’re germinating seeds, planting several in one pot is beneficial. Even in the best growing conditions, not every seed will produce a sprout. So, we try to germinate several seeds at once to make sure that you have something to cultivate moving forward.
If more than one seed produces a sprout, you will need to thin the herd a bit. It’s best to thin the seedlings when they are about 2 inches tall.
Examine each seedling closely and choose the one that looks the healthiest. Typically, the healthiest seedling with be the tallest and most colorful. If the seedling is struggling to stay upright, it will likely experience developmental problems as it gets bigger.
Once you choose your primary seedlings, remove the rest. Simply use your finger to pull the seedling from the soil. You can also snip them off with shears if you’re worried about root damage.
Remove all of the seedlings until you have just one in the center of your pot.
10. Fertilizer cauliflower plants in pots
As your crop is growing, it will need a bit of extra help in the nutrient department. Cauliflower plants are heavy feeders. In just a few months, the nutrient supply can dry up, resulting in stunted development. You want your plant to have enough energy to produce a large head, so regular fertilization is a must.
Use a balanced fertilizer to feed your plant every 3 to 4 weeks. Go for an organic or vegetable-safe product. Water-soluble formulas are best. All you have to do is dissolve the granules according to the instructions and water your plants.
Focus your watering on the soil around the base of the plant. Try to avoid getting any fertilizer on the stem. The fertilizer could end up burning it.
Continue to apply fertilizer throughout the life of the plant.
If you’re planting from seedlings, wait a few weeks after planting to apply your first dosage. Providing fertilizer too early could stress the newly transplanted seedling. Wait for 3 or 4 weeks. Then, follow a monthly fertilizer schedule.
11. Harvest cauliflower from pots
It doesn’t take long for heads to appear. The tiny vegetable will continue to grow several inches in diameter before it is ready to harvest. But, there is one thing you need to do before you get there.
Blanching is the process of protecting the cauliflower heads from direct sunlight. While the plant loves to bask in the sun, the crop itself is another story. Too much sun exposure will cause the head to degrade in quality.
The iconic sweet flavor turns bitter and unpalatable. Some cauliflower varieties may even develop blotchy patches of purple. It’s not the most appetizing thing to harvest.
Protecting the head from excess sun exposure is not as easy as creating shade. Remember: The rest of the plant still needs as much sun as it can get. You have to get a bit creative to ensure that you’re getting a flavorful harvest.
To blanch your cauliflower, use the large outer leaves. Fold a few leaves around the head like a cacoon. Then, secure the leaves in place with some twine. You can even use clothespins or rubber bands. This process blocks just the right amount of sun while still giving the plant room to grow.
It’s best to blanch the heads when they’re about 3 inches in diameter.
Not all cauliflower plants will require blanching. Some are “self-blanching” and have leaves that curl inwards. Just keep an eye on the amount of sun the head is getting. If the leaves aren’t doing the trick naturally, coerce them into place.
In most cases, the cauliflower is ready to harvest a week or two after blanching. By that point, the head will be anywhere between 6 and 8 inches wide.
Unfold the leaves and give the vegetable a feel. It should be white, firm, and compact. The florets should be close together to create that signature cauliflower texture.
To harvest the fruits of your labor, cut the heads off with a sharp knife. Cut below a few leaves so that you can continue using them for protection.
Freshly harvested cauliflower will last about a week in the refrigerator. If you’re not ready to eat them, you can also cook them briefly in salted water and pop them in the freezer.