De-bugging outdoor potted plants to bring indoors

Pelargonium 'Vancouver Centennial'

 When a recent storm threatened to bring many more days of rain to my plants that had already had several days of rain, I decided to bring them in for a break.  I brought them into the house and the following steps are for that situation.  When bringing plants into a winter greenhouse the steps will be slightly different.  For the most part these were zonal geraniums I brought in as my worry was that they would develop stem rot from too much water in their trays and soil.  I also brought in the potted scented pelargoniums in order to trim them back and check their overall health. I also do this with any potted herbs, cacti or succulents that have spent the summer outdoors.

We have actually had a drought this summer (2006), and then several days of rain.  I'm sure the plants appreciated the first couple days of a steady light rain, but they had become used to being somewhat dry and constant soaking for days is not always a good thing.

However, they do get soaked when I bring them in- to remove any unwanted pests.

The first step is to shake the plants off before bringing them in the house.  Many types of spiders regularly live on plants (which is a good thing outdoors as they keep insect pests to a minimum), but I don't necessarily want them all in the house.  :)  I also remove any blooms that have been open for a day or two.

Daddy-Long-Legs on Americana Red zonal geranium

Next, believe it or not, the plants go in the bath tub.  When bringing into a greenhouse, a galvanized tub might be used, or perhaps the plants would simply be hosed down.  But to remove bugs from plants and their pots that will be in the house, I want to also make sure I limit the number of insects that might be in the soil.  By these I mean Wood lice (roly-polies, water-bugs) and earwigs.  I don't really like them in the soil anyway, but in my area, it's a fact of life that roly-polies and earwigs will hide in the lower parts of clay pots, in trays, sometimes in the soil - particularly in pots that contain plants with very woody root systems.  In addition, we have slugs that like the clay pots (and the geraniums) and millipedes.  I really don't want any of these in abundance in my house.  So, into the tub the plants go! The photo below shows several plants in four-inch and six-inch pots in the tub.

These are scented pelargoniums and two Pereskias in the tub.  The tub is filled with water to the level of the top rim of the pots.  Yes, insects, it's time to sink or swim!  These particular plants are wet anyway from being outdoors, but after filling the tub with tepid water, I also turn on the shower.  I'm actually quite the insect fan and hate to do this to bugs I might not otherwise mind, but it is necessary in order to keep the insects from invading other plants in the house.  I do not use pesticides at all, but rely on predatory insects to keep all insect populations in check, so simple steps like flooding the pots are needed when the plant's environment changes and predatory insects will not be as plentiful.

Running the shower helps in a couple of ways.  First, it rinses off any air-born pollens, it washes off any unwanted pests, and generally with even slight force, it bends the plants over a bit, making it easier to spot such insects as Whiteflies or mealy bugs.  Whiteflies especially like scented geraniums and if they were present, I would have seen them with the plants as they are now, bent over after the shower.  I do check further though, just to make sure.  I run the shower for about five minutes, but I let the plants soak with the water up to their rims for about a half hour.  I do this even when I am preventing waterlogging by bringing plants indoors.  And yes, sometimes I have bug jars handy to save the pests that are fleeing the plants and pots.  I also sometimes add fertilizer to this water, depending on what conditions the plants are coming from.  If these plants had been completely bone dry for a week or more, I would not add fertilizer because it will burn the roots of overly dry plants.

So, they have soaked, they have showered, and now I remove them to a staging area where I have placed their clean and dry plant trays, and I let them dry naturally.  I probably have not eliminated every pest.  However, when the pots are immersed, most pests, if any, either start swimming, or they move to the top of the plants, and in either case they can easily be removed.