Emmalea Ernest, Extension Fruit & Vegetable Specialist; emmalea@udel.edu
In Delaware, fall cauliflower can be transplanted July 20 through August 10. Short season varieties may be successful when transplanted later into August, depending on fall weather conditions.
I tested cauliflower varieties for fall planting in 2019, 2021 and 2022. All three trials were transplanted at the end of the fall planning window, around August 10. Over the three years I tested thirty different varieties. Five of them were in all three trials: Bermeo, Flamenco, Twister, Alcala, and Toledo. The table below lists all thirty varieties and includes information on the number years they were trialed, relative marketable yield, days to harvest after transplant, and percent marketable yield by weight. The yield that is reported is yield as a percentage of the average yield for the five varieties included in all trials; relative yield greater than 100 indicates higher than average performance and relative yield less than 100 indicates lower than average performance.
*Candid Charm developed slight fuzziness in the year it was trialed.
With a planting date around August 10, which is the end of the planting window, shorter season varieties were more likely to be successful. Fall conditions were different in each of the trial years. In 2019, the trial was heat and drought stressed in August and the latest maturing varieties did not produce heads before a hard freeze in late November. In 2021, the season was extended and the last cauliflower from that year’s trial was harvested on December 22. In 2022, all varieties matured before mid-November and longer season varieties performed well.
Varieties also differed in their tendency to develop physiological disorders because of heat, or other abiotic stress. This is best represented by the % Marketable column in the chart. Of the five varieties that were tested all three years, Bermeo had the highest relative yield and the highest percent marketable. Candid Charm had the highest relative yield, but was only trialed in 2019. It was rated as marketable but did have slight fuzziness in most heads.