Yellowing and dropping leaves are often a result of poor light, low temperatures, pollution or even pests. If you spot yellowing leaves on your plant look for other signs of these problems.
The Greenhouse Whitefly is most commonly seen as an adult, but detecting them at a young stage can go a long way towards saving your plant. They are commonly found on plants such as poinsettias, ivy, hibiscus, and lantana. Plant safe pesticides are very effective in removing white flies, but simply vacuuming them is also a good solution.
Setting up traps is a great step to take in an effort to minimize pests on your office plants. It, of course, is not a fool proof plan, but it certainly is a good start. Yellow sticky traps help to catch flying pests, like white flies, and fungus gnats. You can buy them, or simply make your own by cutting bright yellow cardboard, and covering them in a sticky material.
Neem oil insecticide can be used safely to treat office plants for mealybugs, aphids, whiteflies, thrips and fungus gnats. Neem oil causes bugs to lose their appetites causing them to starve. Neem oil also reduces female fertility and inhibits reproduction. Consider 2 to 3 applications over a short period of time to affect every life stage.
A common problem with office plants is an infestation of Fungus gnats. Fungus gnats are small, dark-colored flies that jump and fly across the office plant potting soil surface. Studies show that gnats are attracted to vinegar. Fill a jar almost to the top with vinegar, poke several small holes in the lid and then set it out.
The gnats will swarm to the jar, wiggle down into the hole, and will not be able to climb back out. If you set several of these traps around your office and monitor them to determine the highest concentration and subsequently find the gnat source.
If your office plants are dusty or you see a few bugs or gnats, try cleaning your plants with a mixture of 6 oz. of rubbing alcohol, 24 oz. of water and 4 drops of ivory soap. Don't use on African violets. Don't clean more than once per week. Don't apply in direct sunlight.