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Do you know when to Harvest Fennel? The best advice

How to harvest fennel

Fennel is a bulbous vegetable that belongs to the carrot family. A popular favorite in Mediterranean cuisines, fennel is very versatile. It is actually a herb, spice, and a vegetable- all in one. Its bulbous base is often consumed as a vegetable. Whereas its seeds are dried into spices and its leaves are used as herbs. This makes fennel the ultimate plant for your garden.

Many people compare fennel’s flavor to that of anise or expect it to taste like licorice. However, it does not simply taste like licorice. It has a more delicate, sweet, spring-like aroma to it. The bulb as well as the seeds are high in nutrients as well. It has healthy benefits for the heart, and has anti-inflammatory properties due to the presence of antioxidants like vitamin C and quercetin. It even has high fiber content and can relax the digestive muscles. In fact, many ancient remedies used fennel as a relaxant to promote better sleep and fight insomnia.

Fennel growing is an easy, fun and very fruitful activity for any gardener. It is easy to produce and can be provided with the right conditions with zero hassle. Some growing tips as well as knowing when to harvest funnel can be a no-brainer for you.

Types of Fennel

There are two main types of fennel, each with a different purpose; herb fennel and vegetable funnel. If you’re interesting in obtaining fennel seeds, you would want to grow herb fennel. It is also known as sweet fennel because it primarily adds flavor to food.

The fennel herb plant can typically grow up to 3-5 feet tall.  It will grow lots of feathery leaves that can be used as a herb in teas, salads, soups and stews. However, all the parts of the plant are edible. The leaves, stems as well as the seeds are all harvested. You can also use fennel seeds in drinks, sweet dishes, or baked goods. Dulce, Rubrum and Sweet fennel are all popular and widely used varieties of herb fennel.

The second type of fennel is ‘vegetable fennel’ also known as anise fennel. Some also refer to it as Finnochio or Florence fennel. It has a bulb-like appearance with petioles growing at the base. The white bulb is basically edible and has a sweet licorice-like flavor combined with a crunchy texture. The bulb is used in many recipes and is often grilled, sautéed, or roasted.

This fennel plant will grow shorter in height compared to herb (or sweet) fennel. Victoria, Mantavo, Rhondo and Cantino are some of the most popular varieties of vegetable fennel.

Fennel Growing Tips

You can easily grow fennel in spring or fall and get a delicious crop. If you’re growing fennel for the first time, you might feel confused. But with some important fennel growing tips, you can ace this gardening activity.

Firstly, you should be clear on your intended use for fennel and get the appropriate variety accordingly. Be informed on whether you are purchasing a good bulbous variety or ones made for growing fronds and seeds.

Both types of fennel are grown from seed. You can also grow fennel by transplanting especially in areas with shorter seasons. A full sun, and rich, moist oil with organic matter and a pH of 5.5 to 6.8 are its basic requirements. Keep in mind that soil for vegetable fennel should be more uniformly moist for good production of bulbs.

Spring is the best time to sow seeds for herb fennel as the frost season has passed by then. Whereas, vegetable fennel seeds can be sown from mid-June to July. The cooler days of the late summer season are more ideal for adequate bulb production. Basically, you need to avoid extreme temperatures when growing fennel regardless of the type.

This is consistent with a lot of vegetable bearing plants and herbs. Herbs like basil as well as vegetable plants such as carrots need the warmth of the full spring or summer sun for optimal growth.

Also like the other plants mentioned, fennel needs a well-drained and consistently moist soil. An incosistent moisture throughout its growing process can affect the maturity of the bulbous vegetable itself.

Two important requirements for successful fennel growing can easily be fulfilled by mulching. This helps retain moisture and it also helps fight against weeds. Mulching  helps keep the plant hydrated while not drowning it.

Another important fennel growing tip is to solely grow it. This means it doesn’t really benefit as a companion crop to others, mainly because of fennel being a heavy feeder.

One way to get the most out of a herb fennel is pruning. Pruning is an effective method of getting leafy herbs to be more leafy. It is proven to work on various herbs like basil and thyme.

Pruning is a pretty straightforward practice. You can use the deadheading technique (removing the flowers of the plant) to prolong the supply of leaves on your herb fennel. You can also cut the old, dying or diseased flower stems so the plant does not waste nutrients on them. Dead or dying foliage is also a great key to flourishing the volume of the leaves.

When to Harvest Fennel

Vegetable fennel typically needs 90 to 115 days of frost-free season to mature.

You will know when to harvest fennel when the bulbs have grown around the size of a small tennis ball. It’s best not to let them grow larger because this may encourage bolting and ruin your produce, making it go bitter. Simply use a sharp knife to cut the bulb right at the soil line.

When it comes to herb fennel, it takes around 65 days of growing after which you may harvest it. Some varieties may take 10 days less. As needed, you can cut the feathery growth of foliage on the plant, and use or store it.

If you want the seeds, let the plant flower and you can harvest the seed pods when flower heads turn brown. Then place it in a bag and hang it upside down in a cool area with good ventilation. Seeds will soon drop from it, and then you can clean and store them. If you also want to store the foliage, you should dry it first.

Growing Fennel in Pots

Many people wonder whether growing fennel in pots is actually possible and will lead to a successful yield. The answer is yes, provided it has the right conditions to thrive. One important requirement is a large sized pot or container with lots of depth- around 12-14 inches.

When growing fennel in pots, remember to leave some space between the pots’ rim and the soil. One tip is to plant the fennel in a long grow bag with a rolled down top. As your plant grows, you can keep unrolling the top and make additional space for more soil. Basically, you have to ‘earth up’ i.e. pile more soil around the bulbs as they grow. This helps to protect them from the sun.

The soil also needs to be moist, so you must regularly water it. But don’t water-log it, and make sure the soil is well-draining.


Fennel growing is super productive. After all, fennel has so many uses and its’ exclusive flavor is a must-have if you want to spruce up your culinary game. You can routinely enjoy all of its’ health benefits with home-grown fennel around. All you need to know is your intended purpose of growing it, provide it the ideal conditions, and remember when to harvest fennel accordingly.

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