2023 Broccoli Variety Trial Results

Like all heading brassicas, broccoli can be a bit tricky in St. Louis. Broccoli generally needs a pretty long cool season in spring or fall in order to form anything close to the large tight broccoli heads we are used to seeing at the grocery store. As you will know, if you live in St. Louis, a long cool season is anything but assured, particularly in the spring. If the weather turns hot when broccoli is forming its head it will often be small, turn bitter, change the texture, and/or bolt (where the little florets elongate into tough stems and open to yellow flowers).

We have grown many different broccoli varieties over the years and if you pick a fast maturing one you can usually get some broccoli. However, given how large the plants are the yield per area taken is quite small, even if you get side shoots that form after the main head is harvested. So this year we sought out broccoli varieties that had been tested for hot humid areas, or were successfully grown at farms in areas with springs similar to ours and prioritized the shortest days to maturity.

Volunteers with harvested broccoli from our variety trial.


Volunteers with harvested broccoli from our variety trial.

With these selection criteria in mind we ended up growing 8 broccoli varieties, which are listed below.

  1. Castle Dome
  2. Millennium
  3. Gypsy
  4. Lieutenant
  5. Diplomat
  6. Imperial
  7. Eastern Crown
  8. Burgundy Mini Head

2023 was actually a great year for heading brassicas as our spring was unusually long. So all 8 varieties did pretty well. However, 6 of the varieties, Millennium, Gypsy, Lieutenant, Diplomat, Imperial, and Eastern Crown didn’t have harvestable heads until the 3rd or 4th week of June. Although it was still cool in 2023 at that time, it is usually too hot for happy broccoli by the end of June. Because of this, it would be hard to recommend those as reliable producers for a spring planting in St. Louis.

However, Castle Dome and Burgundy Mini Head ripened mid-late May and really impressed us.

Castle Dome

This is our winner in terms of a conventional broccoli. As opposed to the 12-24″ diameter plants that broccoli can produce, it produced significantly smaller plants. Originally we thought this meant they were not happy and would be the losers of the trial right out of the gate. So imagine our surprise when on May 20th these little 12″ plants had 8″ diameter heads on them! Twice the diameter of all of the other varieties we tried (excluding Eastern Crown which also had 8″ diameter heads but on enormous plants). The smaller sized plants allow them to be spaced more closely while still getting a significant amount of food. This is a huge improvement over other varieties we have tried.

It also had impressive holding power in the garden. We noticed it had reached 8″ in diameter on May 20th but didn’t harvest those first heads until May 30th. Despite 10 days on the plant they didn’t bolt and maintained a good texture and taste.

The last thing that impressed us about Castle Dome were its side shoots. After you harvest a broccoli head the plant will usually produce some amount of side shoots, smaller broccoli heads that come up from the stem below where you cut the main head. As opposed to producing a large number of tiny heads, Castle Dome produced a relatively small number of side shoots that were 3″ and 4″ in diameter, the size of the main head of most broccoli we have tried in the past. These side shoots were produced on the plant for about a month after the main head was harvested.


Burgundy Mini Head

The real surprise of the trial was Burgundy Mini Head! It was the first broccoli to be harvested in 2023, on May 20th. However, they actually were ready to harvest before that but we hesitated because we thought they had bolted. Unlike conventional broccoli this forms a loose head that elongates into a bouquet of long-stemmed small-headed broccoli. This is usually the first stage of bolting but Burgundy Mini Head is different. These small purple broccoli heads, along with the 8″ stem they are on a tender, sweet, and delicious. When we realized this on May 20th about a third of the plants were already starting to get tough so they were probably ready in early-mid May. Once harvested these continued to produce side shoots until mid-June.


So if you are looking for a fast maturing broccoli that will produce well in our short spring climate give Castle Dome and Burgundy Mini Head a try!