How to Grow Fennel from Seed (Easy Growers Guide)

Learning how to grow Fennel from seed is an excellent choice if you live in an area where the climate is warm and sunny, then growing fennel will be a breeze. This type of herb does not require a great deal of maintenance. Since the plant grows very quickly, you just need to clip the top of the leaves if they grow too fast for your liking. 

The History of Fennel

The history of fennel is colorful and interesting. The plant was first discovered by the Romans, around the 2nd century AD.

It had been in use as a food and medicinal plant for many years, but its roots were unknown to the Greeks and Romans. It was only after the discovery of the roots that the name fennel was applied to the plant.

As more new fennel varieties appeared it became popular as a culinary herb. The history of fennel, begins at the beginning of the Common Era. Ancient Egyptians and Aztecs used fennel to help reduce their menstrual pains.

The Hindus used fennel to treat diarrhea and nausea. The Chinese, knowing of the herb’s medicinal properties, used it to help relieve congestion and remove mucus from the stomach.

It wasn’t until the Middle Ages that culinary cooks started using fennel seeds for flavoring. In the United States, fennel tea became popular as a condiment for hot and spicy foods. Later, the seeds were added to other cuisines including Italian cooking.

The popularity of the spice waned somewhat, but it made a comeback in the 70s with the resurgence of Italian cuisine. Today, Italian restaurants continue to serve fennel-enhanced dishes.

Medicinal Uses of Fennel

Fennel has been a widely used herbal remedy in the Mediterranean world, since the earliest times. Fennel contains an enzyme called flavan-2-ol, which is believed to be able to suppress appetite, help regulate blood sugar levels, help with allergies and calm overactive bowels. 

Many people believe that Fennel is able to reduce the symptoms of digestive problems such as flatulence and wind, as well as increasing vitality, boosting the immune system, and even lowering cholesterol.

Fennel has been used to treat a variety of conditions, ranging from simple stomach aches and pains, like those commonly associated with indigestion, to serious disorders like Crohn’s disease and inflammatory bowel diseases (IBD).

Fennel tea
Image by congerdesign from Pixabay

Germinating Fennel Seeds

When growing Fennel from seed, the best time to start germination is 2 to 5 weeks prior to the last frost. You can either start germination indoors, or you can directly sow your seeds in your garden. Just place a few seeds in each spot about 1 cm (½”) deep. Seeds should be planted 10 – 12″ inches apart. The soil needs to be at a fairly warm temperature of 68 F, in order for them to germinate.  

If you would like to start them indoors, then the  best way to germinate your seeds, is by using a seed starter tray, and I like to combine this with a high quality seedling mix. Both these products are available on Amazon. 

Fennel seeds will germinate in approximately 7 to 14 days. Seedlings will harden off and will be ready to plant after 4 weeks, and it can be planted outdoors in early-spring.

You will want to keep them moist by misting them with water in a spray bottle daily. 

Selecting a Pot or Planter

Always choose a pot that has holes on the bottom for drainage, and a minimum size of 8 inch or larger, this will allow the plants more room to grow. What you must realize is that smaller pots do not give the fennel plant as much room to spread out and get the nutrients that they need.

When selecting the size of your pot, I would recommend using a pot that is a minimum of 8″ to 12″ inches in diameter. This will give your plant more than enough room, so that the roots can fully expand.

Whenever I grow Fennel I like to use the Classic Garden Planter combined with a high-quality, well-draining soil from FoxFarm. You can purchase both of these products can be purchased on Amazon.

Soil Needed

If you want to grow fennel, one of the best things you can do is to improve your soil. This will provide a better, healthier environment in which the fennel can grow. Fennel is a plant that will grow best in a moist, fertile soil that is well drained, and has been enriched with organic materials such as manure and compost. The proper soil will also help your plants from becoming too woody or bushy, which makes it easier for them to reach full growth.

There are several things you need to consider when choosing the right soil for growing fennel. First, check the pH level. It prefers acidic soil (pH 5.5 to 6.8). If it’s too high or too low, the plants may become too woody or too bushy, which makes it difficult for them to grow healthily. To test the pH level, add a small amount of soil to test its acidity.

The higher the reading, the more acid and alkaline soil your plants need. The pH level can also be tested with a simple test kit. Get it on Amazon.

Proper Watering

When you are learning how to water fennel plants properly, the first thing that you should learn is that the water that the plant needs must be carefully rationed.

Watering is one of the most important steps in growing a productive garden. The best time to water your herbs is in the morning. You can choose to water fennel early in the morning just before you get up or in the evening. When watering, it’s important to water only the area of the soil where the plant is growing. 

Some people mistakenly think that it’s best to water fennel in the same way that they would water a tomato plant. But watering fennel is very different. A tomato plant will need to be watered daily but a fennel plant will only need to be watered once a week. This being said it’s important to know exactly how much water your plants need to stay healthy.

To do this, you will need to water the plant in small amounts at one time so that the roots don’t become damaged. When the plant has been watered, you should then water it again very gently, taking care not to flood the soil.

Sunlight Requirements

This herb likes full sun and will grow well in an area that receives six hours of sunlight each day. When choosing the proper spot for your fennel, you want to be sure that it gets indirect sunlight as well, because that will help it to thrive.

If you choose a spot that has direct sunlight all day, the plant may end up getting burned, or at best, dying because it will not have the proper nutrients it needs. Do not grow fennel in the shade, as this will make it grow thin and leggy.


You will want to learn how to prune a fennel plant because it is a vigorous and fast-growing plant. Some common ways of cutting fennel back are to use scissors, snipping blades. Start off by removing all the leaves on a young plant and then remove any green growth and any twigs as well.

The key to pruning fennel is to keep it small, so pruning back to even nodes is important and the older the plant gets, the more important it is to keep it small and sparse. The first step is to determine where you will be cutting back the fennel.

You can do this while the plant is young and the leaves are still soft, but it is important to do this as the plant matures. When the fennel starts to form and hardens you want to start taking it away from where you’ll be cutting it back. You should be cutting about a third of the stem away from where you want to end the stem, so that the fennel is closer to the ground.

You can then use a sharp knife to carefully cut this hardy stem right at its base. Use a sharp pair of wire clippers to snip the fennel stem at its base. Do not cut through the bark of the fennel, as this can cause the plant to wither. 


A good method to harvest Fennel is by breaking off the tops and leaving the stems on the plant. If you leave them on the plant, they will continue to grow and mature until the roots beneath the stems are covered with a mass of new leaves. Then just pick the fennel as usual and cut the plant from the vine. 

Another way to harvest fennel, is  to cut off the flower heads just above the base. Let the fennel seeds dry in the sun for a few days before removing the leaves. Store the fennel in a cool, dark location. When you decide you want to use fennel in your recipes, you can find recipes using fenugreek as well as fennel.

Companion Plants

Fennel has no companion plants. Be careful where you place it because it will literally inhibit the growth of other plants that are nearby.

Culinary Uses

Fennel is one of the culinary uses for this aromatic herb. Fennel seeds are often used as a flavoring in Italian sausage, lasagna, potato chips, cornbread, salads and other treats. Fennel can be used both as an alternative to garlic when making hot dishes, or as a spice in foods such as turkey, chicken, and fish. It has a pungent taste that some find unpleasant but others love it.

Image by Valter Cirillo from Pixabay

Health Benefits

Fennel health benefits, because of its high iron content, help to improve bone health in both humans and animals. Fennel helps increase the absorption of iron in the intestines, which can improve anemia in people with anemia. It also has trace amounts of zinc and copper in its overall makeup, which combine to improve blood and digestive functions. However, fennel does not provide any fiber, so it is important to consume foods that have added fiber to help your digestive system to work properly.

High potassium content is another of the many fennel health benefits. Potassium aids in regulating water and blood pressure. Potassium helps to control high blood pressure by lowering it, while also lowering the levels of cholesterol in the body.


  • Vince S

    Hello, I'm Vince, and I bring over 25 years of dedicated experience in the world of herb gardening. From cultivating fragrant basil to nurturing hardy rosemary, my journey as a passionate herb enthusiast has allowed me to explore the wonders of these versatile plants. Through, I'm thrilled to share my knowledge, tips, and insights to help you embark on your own herb gardening adventures. Let's grow together!

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