Sanitizing plant pots: what is the best way?

(Question)

Thank you for your advice about how to deal with my plant, which had a very bad infestation of scale, and which I decided to simply throw it out, plant and soil… but would like to keep the pot. Is it okay to wash it out with Lysol, or some other product, and safely start a new plant in the pot. I don’t want it to get scale too.

(Answer)

Thank you for following up, and this is a very good question. All gardeners experience a bit of attrition from time to time, with our challenges with pests. But it is not always necessary to toss the pot, as well. In fact, the process of sanitizing your pot can be fairly straight forward.

You didn’t mention what type of pot you have, but let’s talk about both clay/terracotta, and sturdy plastic pots. First, rinse any residual soil out of the pot with water. Scrub stuck-on soil — and potentially harmful mineral deposits — from both the interior, and exterior, of clay pots, with plain steel wool, or a stiff brush. Plastic pots usually rinse clean with a minimum of scrubbing.

Fill a tub, or large bucket, with 9 parts cool water, and 1 part ordinary household chlorine bleach. For example, this would be 2 tablespoons, to 1 quart of water. Use a tub large, and enough water, to fully submerge your pot.

Soak the pot in your bleach solution for at minimum of 10 minutes, but, while you’re at it, why not make it an hour or longer. Then, soak clay pots in a rinse of clear water for two hours. Porous clay can absorb the bleach solution, but soaking removes it. Rinse plastic pots with clear water to remove any bleach residue.

Chlorine is an unstable compound, and dissipates into water and air quite readily. Just rinse the containers under clean water and set them aside to air-dry. When the containers are thoroughly dry, the chlorine will be gone.

As an alternative, after the scrubbing, terracotta /clay pots — not plastic! — can also be placed in the oven to sterilize them for an hour, at 200 degrees Fahrenheit. Personally, I prefer the soaking/ rinsing method, because at that point my pots have absorbed as much water as they can, which is exactly what I want for my new planting medium, and my new plant’s roots !

Maintenance and cleaning of pots and containers is a healthy regime, not only when gardeners have concerns about passing along one pest to another plant, but also recommended, on an as-needed basis, to prevent unhealthy amounts of mineral deposits from harming your plants’ root systems.

All the best with your “revitalized ” pot — and with your new plant !