7 Heat-Tolerant Broccoli Varieties to Plant in June

Delicious and nutritious, few vegetables can compete with broccoli’s satisfying crunch. Broccoli is a cruciferous vegetable, and it’s usually best grown in cool weather. In cool climates, it’s usually started in late winter and matures sometime in mid-spring. In warm climates, fall planting is best to get the best growth. 

Most types of broccoli need to grow in cool weather because they bolt when the temperature rises. Bolting can also happen as a result of other stressors, like inconsistent watering, but heat is the most common cause. As the temperature rises, many varieties are prone to flower early and go to seed. 

As broccoli flowers, it becomes bitter and inedible. Because of this, many gardeners don’t bother with it during the warmer months. However, several types of broccoli tolerate heat much better. Through breeding, these varieties tend to mature faster, so you can plant them later in the year and have a harvest before the weather is too hot to support their growth. 

If you’re concerned you waited too long to plant broccoli, the good news is that you can probably still grow one of these heat-tolerant types. Make sure you get moving on these soon, though, because time is quickly running out. Give your broccoli a touch of afternoon shade and keep the ground cool and moist. 

Di Cicco Broccoli Seeds

• Prolific producer
• Encourages side shoots
• Versatile use
• Great for freezing
• Classic Italian variety

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Burgundy Broccoli Seeds

• Extended harvest window
• Abundant side shoots
• Tender and flavorful
• Fusarium yellows resistant
• Encourages pinching

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‘Di Cicco’

	botanical name Brassica oleracea var. italica  ‘Di Cicco’
	sun requirements Full sun
	height 2’-3’
	hardiness zones 2-11

‘Di Cicco’ is a tasty Italian heirloom variety that produces a ton of compact heads in a hurry—or at least until it gets too hot. It takes less than two months to mature and continues to produce these small to medium-sized heads well into the summer months. 

The size of the heads means that they mature quickly, and there is little worry about them bolting before you can harvest. Harvest often to keep them putting out shoots, producing even more florets. ‘Di Cicco’ freezes well; when you’re ready, let it go to seed. The seeds from this heirloom have an excellent success rate and will be ready to plant next year!

‘Eastern Crown’

	botanical name Brassica oleracea var. italica ‘Eastern Crown’
	sun requirements Full sun
	height 1’-3’
	hardiness zones 2-11

‘Eastern Crown’ is another early-maturing, heat-tolerant broccoli variety with compact, deep blue-green heads that hold up well in the garden. This is a great type for East Coast growers. It matures in two to three months, and the compact plants produce an ample number of heads. 

In cool climates, you can plant ‘Eastern Crown’ right up into the summer months. This hybrid went to market in 2020, so it’s a fairly new cultivar. In warm climates, wait until late summer to early fall if you want to plant for a fall and winter crop. 

‘Green Emperor’

	botanical name Brassica oleracea var. italica ‘Green Emperor’
	sun requirements Full sun
	height 1’-3’
	hardiness zones 2-11

‘Green Emperor’ is another heat-tolerant hybrid that works well in warm climates and is great for summer-season greens in cooler climates. It’s well adapted to long daylight hours. This variety is a vigorous grower that produces a great quantity of small, nicely shaped, uniform heads. 

Another nice quality of ‘Green Emperor’ is its extended storage life. It takes just over two months for it to begin maturing. Broccoli is a cut-and-come-again vegetable, so you can continue to harvest it for an extended period. Harvest before your heads begin to flower to keep the plant producing rather than going to seed.

‘Imperial’

	botanical name Brassica oleracea var. italica ‘Imperial’
	sun requirements Full sun
	height 1’-3’
	hardiness zones 2-11

‘Imperial’ is by far one of the most heat-tolerant broccoli varieties around. In fact, it prefers some warm temperatures to produce dense, robust heads. You can grow this variety in spring, summer, and fall in cool climates, and through the winter in warm climate regions. 

In terms of storage, ‘Imperial’ also ranks among the best. The heads are dense and sturdy, with a delightful crunch. The beads are small and dark blue-green, and the plants grow to a stately height. In warm weather, it will mature a bit slower.

‘Green Magic’

	botanical name Brassica oleracea var. italica ‘Green Magic’
	sun requirements Full sun
	height 1’-3’
	hardiness zones 2-11

‘Green Magic’ has excellent qualities. It’s an early maturing variety that produces heavy, sturdy heads and tons of side shoots. It’s also a dependable cultivar. You can count on this one to produce uniform, domed, high-quality heads. 

When growing broccoli during the warmer months, it’s a good idea to plant in a location that gets some shade in the afternoon. Afternoon sun is extra hot and intense, and will heat the ground faster. Morning sun is best in this case. Make sure your plants get plenty of water as well. 

‘Sun King’

	botanical name Brassica oleracea var. italica ‘Sun King’
	sun requirements Full sun
	height 1’-3’
	hardiness zones 2-11

If you’re looking for large, robust broccoli heads, ‘Sun King’ is the one to grow. Surprisingly, this is not a large plant, but the heads certainly are. At six to eight inches, these are the largest on the list. After harvesting the main head, this plant will continue to produce tons of side shoots for continuous harvest. 

As a smaller plant, ‘Sun King’ is a great container variety. Grow this one in your raised beds or in a pot, or put it right in the ground. It’s always on the list when heat-tolerant varieties are the topic. Keep the soil consistently moist, but don’t allow it to become waterlogged, or you’ll end up with yellow leaves and potential crown rot. 

‘Burgundy’

	botanical name Brassica oleracea var. italica  ‘Burgundy’
	sun requirements Full sun
	height 1’-3’
	hardiness zones 2-11

‘Burgundy’ is a heat-tolerant sprouting broccoli variety. That means it produces a smaller main head, and before growing tall and producing an abundance of substantial side shoots. It’s tolerant of much warmer temperatures than traditional broccoli, so you can continue to harvest throughout most of the summer months.