IPM Basics

IPM, intergraded pest management, is the practice of long-term prevention and suppression of pests.  Several tools are commonly used, including scouting, resistant varieties of plants, and cultural practices. Pesticides are only used when pest pressures have reached an unacceptable level for the situation, and even then products are selected that are environmentally responsible. 

Initial Prevention- It is well known that when a plant is grown in optimal conditions, it is less likely to have insect and disease problems, but why? 

Two things can cause stress factors; a lack of essential resources, or an inability to utilize those resources.   A  plants’ natural resources are primarily light, water, temperature, and nutrients.  An example of an inability to utilize resources would be when there are adequate nutrients present, but the soil pH is too high or low, preventing uptake.  The more stress factors you have the greater the chances of pest problems. Also know where your plants come from.  It is going to be an uphill battle if you plants are not healthy to begin with. 

Once a plant becomes stressed the levels of "built in" pesticides declines in the plant and pests can move in.

Heliconia in bloom

Spathyphylum in nursery in Lake Worth, Florida

Maintenance to Prevent- My rule of thumb here is “More is not better”.  It is so tempting when watering, or even fertilizing a plant, to “add some extra”.  If your thinking is this will help the plant to better health, think again!  Too much fertilizer might push the plants to grow too fast in an Interiorscape (having to replace sooner), or even create phytotoxicity issues.  Growing too fast may also cause a decrease in the concentration of plants’ allelochemicals.  Also keep in mind that plants in an interior area do not get their soils flushed like plants outdoors or in nursery settings.  This lack of flushing will allow a build up of nutrients and salts in the soils, so they must be monitored closely.  Soil and leaf tissue analysis will let you know if there is a nutritional problem and whether it needs to be treated.  But what does this have to do with bugs?  These factors can stress a plant, thereby making it more susceptible to insect damage.  Proper nutrition is essential for prevention of pest problems and sometimes this may mean not feeding the plant at all!

Treatment of problem- So you have tried to do it all right: adequate light, proper watering, and good nutritional practices.  Despite your best efforts, somehow “Poof” like some kind of magic “they” appear in the middle of the night.  You stand there scratching your head asking yourself  “ How did they get here, and at such high populations?”   Well it is not magic.  It is possible that the insects came in on the plant hiding in a leaf fold or even in the soil.   A neighboring plant that can sustain this pest without signs of damage may be the culprit.   Insects and mites can move on wind currents, peoples clothing, and tools, so these could be other possible sources.  This is why scouting your plants and keeping records of pests found is so important. Want to learn more about scouting? click here. By keeping records they can be of long-term benefit as many pests tend to appear at about the same time each year.

In the short run the records will let you know if the pests survive a control method be it chemical/ biological/ or mechanical.  If the control method didn’t work you will be better equipped to analyze the situation to find out if the problem was poor timing, poor application, or pesticide resistance in the pest population. 

Scouting for pest problems