It pains me to even write about this, but sometimes a fig tree needs to be removed. Maybe it got too old or too big, and maybe it died on its own. Whatever the reason is, removing the tree itself isn’t the hardest part. The hardest part is making sure the roots don’t continue to grow and spawn new suckers.
How to kill or remove fig tree roots?
Fig tree roots can be removed by digging them up or killing them with herbicides, salt, or vinegar. It’s best to dig them up, but the most difficult at the same time. Herbicides, salt, and vinegar are easy to apply, but they require time and repetition to kill fig tree roots.
Why Is It Important To Remove Fig Tree Roots?
Some want to remove fig trees because they started to do damage to their house or sidewalk. However, many of those people forget to remove the roots, and the damage continues. Even if root damage wasn’t the main reason for removing the fig tree, the remaining roots could still cause problems.
The remaining roots may find a source of water or fertilizer from underground pipes and start growing uncontrollably. Then, new suckers start growing all over the place, destroying other plants.
Fig trees are vigorous; I would even say stubborn. They fight for survival as long as there are proper conditions for their growth. The growth is triggered by many things, including a dry, warm climate in spring and summer. I found that to be the key condition on which the fig “decides” if it wants to grow or not.
We will see later how we can use this to our advantage when trying to stop fig roots from growing.
Digging Up Fig Tree Roots
I think that digging up fig tree roots is the way to go if it is possible. Sometimes, there is other important vegetation around which blocks you from accessing all the roots. Maybe roots even go on someone else’s property, and you are left with no choice but to use root killing methods.
All in all, fig tree roots spread wide, but most of the time don’t go deep. If they are accessible, digging them isn’t nearly as difficult as most think. You don’t even need to remove all the small roots, as long as you remove all the shallow ones.
How deep you need to dig, depends on the climate. In dry climates, you need to dig a bit deeper, while in wet climates, roots and new growth start rotting before they can reach the surface. In my experience, roots deeper than 3 feet can be left in the ground.
Now, onto the digging procedure.
I dig around the stump first, cutting all the main roots with a sharp spade shovel. Once the side roots are disconnected from the fig tree trunk, I use the sharp side of a pickaxe to dig canals along the main root lines.
Cut all the small roots going away from the main ones, and then you can start pulling them up. Ficus tree roots are tough to pull up when there is a whole net of them, but they come out quite easily once you cut them apart.
Very thin roots can be left even in shallow soil. They won’t trigger new growth. Once there is a large enough diameter around the stump, you can use the flat end of a pickaxe to cut roots beneath and remove them. All the roots which are going down can be cut to about 1.5 feet and left there.
Additionally, if they are strong roots, you can use herbicide, salt, or vinegar to poison them just to be sure.
Killing Fig Tree Roots With Herbicide
One of the most recommended methods of killing fig tree roots is herbicides. Although, from my own experience, I would advise using them only if there is no other important vegetation along with the roots. Herbicides are very toxic, and they tend to poison other herbs and trees as well.
Herbicides containing high amounts of triclopyr are the best at dealing with fig tree roots. I’ve used Triclopyr 4 EC and Hi-Yield Triclopyr Ester from Amazon. Both proved equally good as they contain the same amount of triclopyr.
From other herbicides, I’ve tested Stump-out by Bonide. It worked well but took longer to kill all the roots. Although, that might’ve been due to some other conditions as well.
It’s best to apply herbicides through the fig tree stump as soon as the tree is cut. If it’s still alive, it will transfer herbicide to the roots more effectively. I make cuts with an ax or drill holes in it. The holes don’t need to be deep because the tree’s vascular system is in outer layers but make sure you remove all the sawdust. Sawdust will absorb the solution, and it won’t be nearly as effective.
To finish off, I pour one of the herbicide solutions mentioned above into the holes I made.
It’s best to cover the stump with plastic wrap to keep the solution from washing away in the rain. Repeat the process once a week until results start to show. Herbicides usually take 14-30 days to destroy all the roots.
Killing Fig Tree Roots With Vinegar
You can remove fig trees with vinegar, or at least some people I know say they can. I haven’t tried it myself, but from my understanding of fig trees, it must work.
Fig trees can withstand high pH, but even though they thrive in slightly acidic soil, they die once it becomes too acidic. Because of its acidic nature, vinegar will kill the roots. However, this acidity can harm the soil and other plants in the long run. However, you can counter the acidifying effect later on.
So, if you’re going to use vinegar to kill fig tree roots, make sure you neutralize it soon afterward. To balance the pH of the soil, you can use an equally powerful base like bicarbonate or limestone.
To apply vinegar, use the same method I explained above with herbicides.
Can You Use Epsom Salt To Kill Fig Tree Roots?
Epsom salts are generally used as a magnesium source for soil. Since fig trees greatly benefit from magnesium, it’s a popular belief that Epsom salt is a universal remedy for fig tree problems. However, that benefit works only if the soil is magnesium deficient, and adding it without doing any tests can harm the tree.
We can use those same harmful effects to kill fig tree roots. Salts, in general, kill all the plants in higher quantities.
Unlike vinegar, I’ve tested killing fig tree roots with salts, and it works. Although, they are not as effective as herbicides. Epsom salt specifically works a bit better than other salts because fig tree absorbs bigger amounts of it due to its need for magnesium.
To kill fig tree roots with salt, use the same method as with herbicides.
Killing Fig Tree Roots Using Cardboard
I’ve had great success with cardboard. It works excellent; however, to achieve perfect results in dry, warm climates, you need to use it together with some chemical solution. It’s best used in late winter or early spring because the cardboard decomposes quickly, and you want to use it at that crucial moment when new growth starts.
It works because it shields the stump from the sun, which triggers new growth. I’ve used it to kill smaller plants and wild grass beneath the tree. On a fig tree stump, I would have to keep a close eye on it because this is a novel experiment, and it needs to be monitored. Its effectiveness depends on climate conditions.
The best thing about cardboard is that it’s 100% decomposable, which means there won’t be any adverse effects on soil.