How to grow broccolini at home – for substantial harvests of gourmet vegetables

Broccolini has become a very fashionable vegetable in recent years, often seen on the plates of high-end restaurants and fetching a premium price in grocery stores. But what exactly is broccolini and can you grow this trendy crop at home?

If you grow broccoli in a backyard vegetable garden, you know it has a short season. You get one main head to harvest and then hopefully a few more side shoots will follow. However, the joy with broccolini is that you get a bounty of bite-sized stalks and heads over a long harvesting period.

I grew and harvested broccolini for chefs at a Michelin-starred restaurant when I ran a walled vegetable garden and have seen first-hand how productive the plants can be. My plants were grown from seed in a greenhouse and planted in late spring to give a long harvest of delicious stalks. See how you can grow broccolini too.

What is broccolini?

Broccolini is an annual plant in the Brassica family and a hybrid between European broccoli and Chinese broccoli, also known as gai lan. It goes by many names, including tender stem broccoli and aspabroc, but is often known by its common name of ‘baby broccoli’. The crop resembles traditional broccoli but produces many small shoots rather than one large head. The entire plant is edible, including the florets, stems, and leaves.

How to grow broccolini - from seed or transplants

If you want to add broccolini to your growing list for this year you can buy transplants from garden centers, nurseries, or online to plant in your vegetable garden. Alternatively, you can add the crop to your seed sowing plan and grow broccolini from seed.

How to grow broccolini from seed

It is best to sow seeds indoors and grow your own broccolini transplants. This should be started 4-6 weeks before your last frost date. Sow seeds into individual pots filled with quality potting soil for starting seeds, available at Walmart, and start them in a warm and protected place - such as in a greenhouse or on a bright windowsill.

Transplant seedlings into the vegetable garden when they are around 4-6 weeks old and after the risk of frosts has passed. The seedlings want to be hardened off for a few weeks to get used to outdoor conditions.

A second sowing of broccolini seeds later in the year can provide a fall harvest. Sow seeds in mid-to-late summer and transplant the seedlings into the garden once they have 6-8 true leaves and are large enough to handle.

You can sow seeds outdoors directly into their growing position. Prepare the site by weeding and raking it level and sow seeds a half-inch deep once the soil temperature reaches 55°F. When the seedlings appear, thin them to around 12 inches apart. Slug control may be required, as the pests can be an issue due to their tendency to eat seedlings as they develop.

How to plant broccolini

Broccolini plants are cold-sensitive and should only be planted after the last frost date for your location. Jessica Mercer from Plant Addicts advises growers to wait until ‘the soil is workable in the spring’ to plant out. She adds: ‘Broccolini is more sensitive to frost than broccoli. So cover your broccolini if an unexpected frost occurs after planting.’

As broccolini plants are sensitive to low temperatures, protect young vegetable plants from cold nights and light frosts with horticultural fleece, available at Amazon. The plants can suffer damage at temperatures below 25°F.

Broccolini plants can grow relatively large and should be spaced 18 to 24 inches apart. Plant them in a sunny spot in your garden, ideally one that receives at least 6 hours of direct sunlight. Broccolini plants can tolerate partial shade, however, this will impact the quality of the spears come harvest time.

An ideal soil type is fertile and well-draining with a slightly acidic pH for best results. It is beneficial to add compost or well-rotted manure to the planting site. Mulching the plants will aid in retaining moisture and controlling weeds.

Jessica Mercer

Jessica Mercer, PhD, is the senior content marketing coordinator for Plant Addicts. As a 'plant collector', Jessica enjoys growing many different plants and learning about the best culture practices for each. Writing for Plant Addicts is a real joy for her, as she can use her science background to research interesting plant topics

Care tips

Broccolini requires lots of watering to grow strongly and produce a great harvest of tasty spears. Pay regular attention to when to water plants, as broccolini wants about 1-2 inches of water per week to keep the soil consistently moist.

The crop also benefits from regular feeding during the growing season. As Jessica Mercer advises: ‘Broccolini is a hungry and thirsty crop. Fertilize crops every three weeks with a balanced organic formula, and avoid products that are high in nitrogen.’

As with all brassicas, broccolini are susceptible to pests including cabbage loppers and cabbage worms. The best way to keep caterpillars away from the vegetables is to cover plants with fine garden netting, available at Amazon. Any caterpillars can be picked off by hand or organic insecticides that contain the natural bacteria Bt (Bacillus thuringiensis kurstaki) can be sprayed to control the pests.

The likes of aphids, flea beetles, and thrips can also affect broccolini plants. Covering plants can combat many pests and spraying affected plants with insecticidal soap, also available at Amazon, neem oil, or simply a jet of water can help.

How to harvest broccolini

Broccolini can take 50-60 days to go from planting out into the garden to being ready to harvest. The central crown can be cut when it develops, this is edible but the primary reason for removing it is to stimulate the growth of lots of side shoots.

The side shoots will develop quickly from the stem and should be harvested regularly when they are around 6-7 inches long. Cutting these florets back to above a set of leaves will promote the continuous growth of lots of more stems. Regular harvesting will provide you with a bounty of delicious shoots and prevent the plant from flowering.

FAQs

Can you grow broccolini in pots?

Broccolini can be grown in pots as part of a vegetable container garden or in raised beds - you can enjoy this fashionable crop even in a small vegetable garden. Any container needs to be at least 16 inches wide and have holes in the button for drainage. Keep a close eye on watering plants in containers as they can dry out quickly, especially in the summer.

Can I eat broccolini that has flowered?

When broccolini has yellow flowers it means that the vegetable has matured and started to bolt. Warm weather often causes broccolini to bolt and produce these small yellow flowers. The whole of the plant is edible, including the flowers which can be added to a variety of dishes.

The cut-and-come-again nature of harvesting broccolini means you benefit from a long cropping season. Planting such crops in a kitchen garden gives you extended harvests and a bounty of homegrown veg from one plant. Other brassicas that will continue to produce a crop once you start harvesting include kale, broccoli rabe, and purple-sprouting broccoli.