Common House Plant Pests - Part 4: Mealybugs - Planococcus citri

I was asked to rescue this Jade plant (Crassula ovata) for a friend. They were wondering what the white stuff was covering the base of each leaf.

This Jade plant has seen better days. Leaves are distorted, the growth is weak; becoming susceptible to attack. Every leaf axil was invested with Mealybug. Their typical white, powdery coating is a dead giveaway. Female adults are hidden beneath, sucking sap from the host plant.

A close up, showing white fuzzy cotton insects at each leaf node (joint).

I hate using chemicals. High pressure water is by far my favourite control for Mealybug. Don't worry about damaging leaves. The spray from a garden hose is not that harsh. Don't use a pressure washer, just a hose attachment for the garden.

* Note: Be sure to spray on a driveway or area where the Mealybugs cannot transfer to another plant. In the summer months, Mealybugs can easily survive and find other hosts in your garden.  Treat your plant in this manner on a hot summer day. The Mealybugs will fall to the pavement and because their food source is gone, they will die in the hot sun.

Use either the Jet or the...

Flat setting on your hose end sprayer.

Liberally spray the plant in all directions. Under the foliage, on the top of the foliage - reaching all the nooks and crannies. This pressure will help dislodge leaves that need to come off anyway. Not to worry.

After you've sprayed the plant thoroughly with water, make sure any dislodged Mealybugs that have fallen on the top of the soil in the pot is also sprayed out.

Soil is generally compacted enough in pots. Spraying this hard won't wash all the soil away. Spray on an angle and tip the pot if necessary.

Spray the saucer on both sides thoroughly. The more thorough you are, the less likely the Mealybugs will return.

Spray the pot, under the rim, beneath....EVERYWHERE. Mealybugs are persistent and they hide in any corner, nook or crack.

Remove any damaged, old, wrinkly leaves. Be sure to spray with water at the leaf axil after leaves have been removed. Eggs or small, in-star Mealybugs may still be there.

Use rubbing alcohol as an additional control after you've thoroughly sprayed the plant. Apply with a cotton swab and paint the leaf axils, buds, bases of the leaves/stems.

Be sure to get all the leaves, axils and any where you may have noticed Mealybugs before the treatment. It's an arduous task, but worth it. You can actually kill off the Mealybug by painting alcohol over its body. It kills them on contact. The alcohol removes their outer white coating and makes their exterior skin dry out.

After painting all the leaf axils and other areas you may think the Mealybugs have been, wipe the pot down with a cloth drenched in rubbing alcohol or a bath of 1 part rubbing alcohol to 3 parts water and 1 tsp dish soap. This will prevent eggs or crawler bugs from surviving.

An alternative is to repot with a sterilized/clean flower pot. If you do so, be sure to clean the former pot and store in an area where if any Mealybugs were to survive, they would soon die off from lack of any food source.

Once you've treated your plant, resituate in a bright area, away from other house plants until you know the infested plant is clear. Add a layer of fresh potting soil and use houseplant fertilizer every two weeks when watering. Monitor your plant every other day for re-infestations. Retreat until no more Mealybugs are to be found.

In the winter, Mealybugs don't like the cold. If you can't spray as I did on the driveway but you want to kill off the Mealybugs; bring the infested plant towards a cold window sill. The Mealybugs will move away from the coldest side of the plant to the warmer leaves. Once they congregate, remove with a cotton swab doused with rubbing alcohol.

Hope this helps.

Check out my updated post on the results!