There are 3 different chemicals that can be used to get the job done and the process is the same for all of them.
You can use one of the following:
- Potassium nitrate (Fast)
- A fertilizer high in nitrogen (Fast)
- Bleach (moderate)
- Epson salt (Slow)
- Rock salt (slow)
If you are looking for the safest method if you have dogs, cats, or even kids roaming around your backyard, I suggest either Epson salt or rock salt.
Tools needed for the job
- Drill and a large bit
- Plastic cover or tarp
- Hand saw
- Garden mulch
Personal protective gear
- Steel-toed boots
- Safety gloves
- Eye protection
Step by Step Guide
Step 1 – If it is not done already, cut the stump down as close to the ground as possible.
Depending on the size you will need a chainsaw or handsaw. The less stump to rot the quicker the process will be.
Step 2 – Next drill holes as deep as possible. Keep the holes a couple of inches apart and cover the whole top of the stump.
Step 3 – Next you need to select which chemical you want to use. You will need to first pour water into these holes. The water is needed to start the chemical reaction.
Then add a very generous amount of one of the above chemicals.
Step 4 – Once done you will need to cover the stump with your plastic cover or trap.
What we don’t want is moisture escaping, so the tarp will keep everything moist which allows the chemical reaction to continue for months on end essentially dissolving your stump.
Step 5 – Next, cover the plastic trap with wood-chip mulch then water the top and surrounding area. This will ensure that the chemicals would have adequate moisture to work and prevent them from drying out.
Step 6 – Every 4 – 6 weeks you will need to repeat steps 3 – 5, uncovering the stump, pouring more chemicals on the stump, watering then covering back up again.
If you opt for the harsher chemicals like potassium nitrate, you will need to check every 2 weeks or so.
Step 7 – As you uncover the stump to add more water and chemicals you will notice the rotting timber will be soft and spongy.
You will need to remove this with an ax so the next batch of chemicals is attacking fresh timber and not being wasted on the already rotting timber.
Once the stump has rotted down to ground level, you can pour one last large batch of chemicals and leave it to decay beneath the ground.
From woe to go the whole process will take anywhere from 6 weeks to 12 months depending on the chemical you use and the size of the stump.
Can you really use salts for rotting a tree stump?
Ideally, the use of chemicals for rotting a tree stump is discouraged because it is a relatively harsh choice. It may even be illegal in some states. Rock salt or Epsom salt is a great alternative. They are relatively safe as they are naturally occurring and will not hurt anyone who comes in contact.
The downside is they will take a lot longer to get the job done, so you need to be in it for the long haul if you want to go the organic method.
Another downer with salts is they are deadly to live trees. If the stump is in close proximity or other trees, then I discourage using any chemical method. I would opt for something a little more natural like burning or grinding the stump out.
How long would it take?
As mentioned, rotting a tree stump can take anywhere from a few weeks to an entire year. This entirely depends on the condition of the tree stump when you start, the size of it, and the chemical you are using.
Naturally, if you are opting for a more aggressive chemical such as Potassium nitrate or a fertilizer high in nitrogen, then it’s going to speed up the process.
On the other hand, using salts such as Epsom salt is going to take longer to work because it’s a more natural and slow process.
There are other alternatives for stump removal, such as burning the tree stump altogether or hiring a stump grinding machine from your local Home Depot and doing the job yourself. It will be done in an afternoon and you won’t be using any harsh chemicals that could harm other trees close by.
What about organic methods
You have three main options when it comes to getting rid of a tree stump naturally.
You can either burn it or dig it out or get in a professional stump removal service.
Like all things organic, it costs more. The cheaper method of doing things is cheaper a lot of the time, but if you care for the quality of your garden and the soil, I advise getting a stump grinder in the do the job.
There are no chemicals involved and the stump will be gone in about 30 minutes. It will turn your stump into a wood-chip which you can then use in your garden.
Do chemicals ruin my garden?
If you are looking to plant something in the place of the stump you are removing, or even anything nearby, contaminating the soil with harsh chemicals will not do you any favors.
It could be years before your soil is in the right condition to even grow grass over the top, let alone a new plant.
Even something like salt is fatal to trees. Trees absorb water through osmosis as their roots have a high salt content. If you increase the concentration of salt in the soil, it sucks the moisture out of the plant and they die.
If the soil remains salty then nothing will grow.
See here for a price list of sump removal services by stump size.
What’s the best method?
If you are after speed then rotting your tree stump is not the solution, you are the best burning or getting a stump grinder in.
If you are after easy and relatively fast, then I suggest you either burn the sump out or use potassium nitrate to rot the stump quickly.
If you are after something less harsh that is pet friendly I would go with the salt method, but if you want total organic, then I suggest you get in a professional to grind the stump out or hire a grinder and do the job yourself.