Broccolini, Brassica oleracea Italica × Alboglabra, is a hybridized cultivar made from crossing broccoli with Gai Lan or Chinese kale. It is known to be anticarcinogenic, packed full of nutrients and flavor, more hardy and productive than traditional broccoli varieties, and delightful eaten both raw and cooked.
But it is a demanding plant to maintain, and harvesting must be done correctly, or your efforts will become fruitless. The following article is a guide on growing the new hybrid, including when to harvest broccolini, how to know when it is ready, and how to maintain it during the growing season.
When to Harvest Broccolini
Harvesting broccolini occurs when the head has been formed but before flowering has begun, which is typically 75 to 100 days after seed germination or 60 days after transplanting into the garden. The timing of broccolini harvesting is pivotal because the young stems are the most sought-after when their flesh is young and tender, and they harden as they continue to grow.
Broccolini Growing Stages
The following describes the growing stages of the broccolini plant and includes the growing conditions necessary to maintain the plant during that stage.
Seed germination will take between 7 to 10 days in warm, moist conditions. Start seeds indoors 4 to 6 weeks before your area’s last frost. Place 3 to 4 seeds ¼ inch deep into a seed-starting potting mix. Keep the seedling under a grow light and use a heating pad. Small cotyledons will emerge within a few days and should be up to an inch tall within a week and a half.
Harden your young broccolini seedlings during the week before transplanting outdoors by bringing them outside for a few hours each day, gradually increasing their time spent outdoors. They will be ready for transplanting once the broccolini seedlings have developed at least 6 to 8 leaves and are around ½ foot tall, which is usually within 4 to 6 weeks. Plant the young broccolini plants at least a foot apart to give ample growing room for these bushy herbaceous species.
3. Vegetative growth
During the vegetative growth stage, broccolini will grow rapidly and stretch its stems towards the sun. Broccolini needs full sun, nutrient-rich soil, and at least 1 to 2 inches of water per week. Adding a nitrogen-rich fertilizer at the end of this growth stage is helpful to the plant in its preparations to enter the flowering stage, which is when the head of the broccolini begins to form.
While the entire plant is edible, the side stems of the mature plant are the most commonly harvested. Just like broccoli, broccolini heads are harvested as the flower heads are forming but before flowering begins, which is usually 50 to 60 days after transplanting outdoors. Harvesting encourages broccolini to grow more side shoots instead of going to seed.
Days to Maturity
75 to 100 days after germination, you should be able to begin harvesting your broccolini. This long growing time is the reason why it is essential to start your broccolini plants indoors when you live in colder climates. Once harvesting has begun you should be able to get several rounds of picking done before the first frost arrives. If you bought broccolini to plant that already has well-established root systems, then your broccolini should be ready to begin harvesting within 50 to 60 days after planting. Broccolini is dependent on having the ideal growing conditions to steadily push it past its vegetative stage.
How to Tell If Your Broccolini is Ready for Harvest
Broccolini must be harvested at the correct time to ensure you are receiving the best flavor and nutritional content. Once the main stalk is forming its flower head, then it must promptly be harvested to stop the plant from progressing into the flowing stage. Once the main stalk is harvested, the side shoots will begin to mature more rapidly. Harvest these side shoots as they mature, or as a group at least twice per season.
What Broccolini Looks Like When It’s Ready to Pick
The broccolini plant will be about 2 ½ feet tall when it is ready to be harvested. Begin harvesting when the broccolini leaves turn dark green and the heads are starting to form. The head will resemble those of broccoli heads, only considerably smaller. Do not delay harvesting until yellow flowers begin to form.
Yellow Flowers on Broccolini
Broccolini plants develop yellow flowers that resemble many others that are also in the Brassicaceae family. Unfortunately, if you see yellow flowers on your broccolini plants, then this means that your plants have started to go to seed.
You will no longer be able to harvest your broccolini because the edible heads have progressed into the flowering stage, which is shortly followed by the production of seed pods. If you are looking to harvest seeds for next year’s planting, then you must let your broccolini flower go to seed.
How to Harvest Broccolini
The main stalk, which includes the broccolini head, leaves, and stem, should be harvested first because it will deter the plant from producing showy flowers and going to seed. The side shoots are then harvested up to 3 to 5 times during the growing season until the plant flowers or the first frost arrives.
Cut the young shoots off near the base of the stem and remove them with all of its leaves. This allows more sunlight to penetrate further into the plant, feeding more shoots that will soon be ready to harvest. Always clean and sanitize your equipment after each use so that you lower the chances of exposing the broccolini to bacteria or pathogens that could diminish its growing capabilities.
Encouraging New Shoots
Broccolini is not a low-maintenance crop to grow. It will take consistent watering and fertilization to encourage the plant to continue producing. To keep the plant productive throughout the season you will also need to work to encourage new shoots. During the vegetative stage and once the plants have reached 8 to 10 inches tall, you can begin to mound soil up around the base of the stem, which will encourage new side shoots to develop.
When beginning to harvest, cutting the main stem first is pivotal in encouraging new shoots. It triggers the plant to continue growing instead of senescing. If you were to leave the main stem on the plant, your broccolini will continue on its course of making seeds, which will end the harvesting capabilities for that season.