Thwarting the Fennel Menace

There are a few pleasures in gardening that really make it feel worth all the work. Harvesting a huge batch of fat, happy potatoes is one. Picking up a cured gourd and finding it whole and hard and ready to be made into whatever project you desire is another.
But there is another gardening activity that is not at all about harvesting and food and goodness. No. I’m talking about the satisfaction that comes when you have completely thwarted an enemy.
My Greatest Foe
If you’ve read my blog before, you might have guessed that the enemy I mentioned is Wild Fennel. I literally named it The Worst Weed in the Bay Area. Back then, I didn’t have much encouraging advice. But that was then.
Now I know how to kill it.
Organically.
Without digging for hours in dry, unyielding clay.
The secret is Darkness.
It’s not pretty, but few murder sprees are, amirite?
That Feeling of Victory
Today, I went to check on a few of my fennel torture bags. Yes, some were still holding on, and I carefully repacked them tightly.
But a few were dead. Fully dead. Dry as a bone. Ex-fennel.
And a few even came out of the ground complete, taproot intact. Look at the picture–that’s 2 feet down in the soil if I had tried to dig it out fully.

How to Truly and Completely Eradicate Wild Fennel


Materials:
- 6 mil Black Painter’s Plastic (NOT weed block)
- Yard Staples
- Yard clippers/trimmers
- Staple gun (optional)
- Black bowls from takeout or instant soup (optional)
Process:
- Trim the fennel down as far as you can go, removing all the material and composting it.
- Cover the stump tightly with the black plastic or a black bowl with holes punched in at least two sides near the earth (only use the bowl if the stump is small enough to fit totally inside underneath).
- Use yard staples or (near wooden fences) staples to secure the plastic or bowls in place. You are trying to eliminate light getting to any part of the plant, and stop any shoots from finding their way out.
- Keep an eye on your fennel darkness pods in case of escaping shoots. Remove any shoots that pop up, secure your light barrier again, and wait some more.
- Check occasionally after a few months to see if the fennel is dead. There should be no green or yellow material, and every part of what remains should be dry and brittle. That means success!
Stay Vigilant
While this method will take care of those old-growth fennel monsters, it does not stop new sprouts. Be sure to tear those invasive jerk babies out of the ground as soon as you see them. Fennel cannot be allowed to proliferate!
Bonus tip: This technique also works on Blackberry!
THANK YOU!!! I read your previous article and it mirrored my wretched experience with fennel, but left me with little hope for the fennel forest our SF backyard has become. I bought the poison but was reluctant to use it so it’s been sitting in my garage for a year, unopened. I’m so excited to see you’ve found an organic solution, now it’s time to go to WAR with this beast. *cracks kuckles*