How To Grow Fennel Indoors? A Beautiful Addition To Your Herb Garden

Many easy-to-care, edible plants don’t take a large space to grow and can do well in an indoor container garden. Fennel is one such plant that’ll thrive on your windowsill and balcony without asking for much attention.

The versatile herb is grown for its aromatic leaves, seeds, and also for its flavorful bulbs. If you have a taste for Mediterranean cuisine, you’ll want to save some indoor space for growing fennel.

But how to grow fennel indoors? So, If you’re trying your luck with growing fennel indoors for the first time, here’s a post on all the basics and specifics that you’ll need to get started. Make sure you follow all the tips to turn this experience into an exciting and rewarding one.

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What Kind Of Plant Fennel Is?

Fennel, Foeniculum vulgare, is a versatile edible plant regarded as a vegetable and a herb. Fennel seeds are used in herbal teas as a natural remedy to treat several ailments.

How To Cook With Fennel?

The appealing anise flavor of the seeds and feathery leaves also pairs well with many sweet and savory dishes. Fennel is more common in Mediterranean cuisine, which is where the herb is native.

Fennel is not only famous as a herb for its leaves and seeds but also as a vegetable. A specific type of fennel called the Florence fennel is cultivated for its bulbous stem. The bulb is usually eaten raw in salads or served roasted or grilled. Its feathery, light green foliage attached to the stem can also be included in salads for a subtle fennel flavor.

Whether you’re growing it for the bulb or its leaves and seeds, fennel grows well in limited spaces. It won’t complain about sitting next to a sunny window in a pot and won’t ask for much maintenance either. Florence fennel is grown as an annual, while ‘herb fennel’ is a short-lived perennial that readily re-seeds in the second year.

How To Grow Your Fennel Indoors?

Fennel is an easy-care plant and relatively straightforward to plant and grow. But, if you’re trying it out for the first time, it’s helpful to follow some basic guidelines.

Whether you’re growing it for the bulb or as a herb, remember to choose a good variety from your local garden center. Make sure it’s suited to your climate. Or, you can also plant fennel seeds from your spice rack!

How Much Space Does Fennel Need To Grow?

Fennel is a vigorous grower. It will take quite some space to spread, both below the ground and above it. It can grow to about 4 to 6 feet (about 1,21 to 1,83 meters ) tall, with an 18 to 36-inch (about 45 to 91 cm) spread.

So, choose a container that’s at least 10 to 12 inches (about 25 to 31 cm) deep since it develops an extensive root system. The width should be at least 12 inches (about 31 cm) if you plan on growing two plants. Make sure there are drainage holes at the bottom since waterlogged soil can destroy these delicate plants.

What Kind Of Soil Does Fennel Like?

Fill the container with quality potting soil after you’ve moistened it. Fennel develops deep roots, which is why it won’t transplant well. The better option is to plant it directly into its permanent home rather than starting it in smaller pots. Sprinkle the seeds and cover them with a light layer of soil.

Place the pot next to a sunny window and check the soil moisture every day. Don’t let the soil dry out; make sure it’s evenly moist at all times. It takes about 8 to 14 days for the seeds to germinate, depending on the soil temperature. The optimal temperature for seed germination is between 60 and 90°F (about 15,5 to 32°C).

When To Harvest Fennel?

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Start harvesting the leaves once the plant is about 8 to 10 inches (about 20 to 25 cm) tall. Use sharp scissors or pruners to cut back the plant, and ensure that you don’t remove more than ⅓ of the plant at a time. This gives it a chance to grow back for further harvests.

When it comes to fennel seeds, you can harvest them in the fall. You’ll need to shake the seed heads and place a bowl or a sheet underneath to catch those seeds. But let them dry before you store them in a cool, dark place.

Bulb fennel can be harvested in about 90 days, once it’s about 2 to 4 inches (about 5 to 10 cm) in diameter. Cut the foliage above the bulbous stem and pull out the bulb. But remember to remove the roots before using them.

What Does Fennel Need To Grow?

You now know the basics for growing fennel in a pot. But, before you begin the project, there are some things you should know to get a thriving fennel crop indoors. Here’s what it needs:

How Much Sun Does Fennel Need?

Fennel prefers to grow in full sun. When growing it indoors, choose a spot next to a brightly lit South or West-facing window. If you don’t get ample natural light in your indoor space, grow them under high output fluorescent plant lights, maintaining a distance of 1 foot (about 30 cm) between the plant and the lights.

How Often Should You Water Fennel?

Container soil dries out faster than ground soil. So, make sure to check it every few days and water the plant once the topsoil feels dry to the touch. Always water at the base, preventing the foliage from getting wet.

Extra Care

Once established, it’s a hardy plant that will re-seed and re-grow every year without much extra effort. Once you start with nutrient-rich potting soil, supplemental fertilization isn’t recommended during the growing season as it causes the herb to lose much of its flavor.

What Fennel Types Are Good For Indoor Growing?

There are two broad classifications to choose from – bulb fennel (or Florence fennel) and herb fennel. There are plenty of types in each category, but here are the popular ones:

Herb Fennels

  • Purpureum – With beautiful bronze foliage, this variety is primarily grown as an ornamental.
  • Rubrum – With aromatic bronze leaves, the herb works well for both culinary and ornamental uses.
  • Sweet Fennel – A standard variety available at most garden centers, cultivated for fresh and dry leaves.

Bulb Fennels

  • Victoria – This cultivar is a vigorous grower and bolts slower than most other fennel varieties.
  • Mantavo – Mantavo is well-known for its good yield. Additionally, it’s slow to bolt as compared to others.
  • Rhondo – This is a quick-maturing variety that gives uniformly sized round bulbs perfect for eating fresh or roasting.
  • Cantino – Catino is usually planted earlier than other bulb fennels as it takes a longer growing season. It’s slow to bolt and offers flavorful bulbs that work well in soups and stews.
  • Orion – This cultivar produces thick, round bulbs in just about 80 days. The crisp, tender texture makes it perfect for consuming raw.

What Mistakes To Avoid When You’re Growing Fennel Indoors?

Now you know plenty about growing fennel indoors. But, there are still a few things to note. Here’s a list of things you’ll need to avoid when grow to ensure the best yield and flavor of your harvests:

  1. Don’t overwater the plant. Fennel is a delicate species and will rot quickly if the soil is waterlogged.
  2. Avoid shady conditions when your growing fennel. Fennel is a sun-loving plant, and its growth will be floppy and leggy if it doesn’t get optimal sunlight. If natural light is scarce indoors, consider installing a grow light over the plant.
  3. Avoid waiting too long to harvest the leaves. Once the plant bolts, the foliage will lose much of its flavor and aroma.
  4. Avoid transplanting since it doesn’t respond well to root disturbance. Make sure you plant in a suitably sized container right from the start.
  5. Avoid fertilizing the plants during the growing season. Nitrogen-rich fertilizers may boost the foliage growth but will cause it to lose much of its flavor.

How To Grow Fennel Indoors? – In A Sealed Package

Temp Required60 To 90°F (About 15,5 To 32°C)
Sowing TimeSpring And Summers
Type Of SoilWell-draining, Compost-rich
Transplanting TimeIf You Want To, Set Out In The Garden After The Last Spring Frost.
Harvesting Time60 To 70 Days, Once The Plant Is At Least 8 Inches (About 20 cm) Tall
Light DurationAt Least 6 Hours
WateringMaintain Even Moisture
FertilizationNo Supplemental Fertilization Needed

Final Words

So you see how easy it is to sow, grow, and harvest fresh fennel without stepping out of your home? With this guide on how to grow fennel indoors, you can start growing your favorite varieties right away and bring new flavors to your everyday meals.

Harvest the leaves as needed in the kitchen for the best flavor. You can also store them in an airtight container or refrigerator to use in the coming few days.

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