Do you have a relative who criticizes the neglected condition of your African violets (Saintpaulia ionantha) every time she visits, in addition to pointing out the other deficiencies in your housekeeping? You can beat Auntie Inflammatory at her own game by using one of her traditional cleaners and cure-alls, vinegar, to grow healthier plants than she does. If she inquires about your methods, you can tell her they are a family secret -- from the other side of the family.
Souring the Soil
African violets must be grown as houseplants in all U.S. Department of Agriculture plant hardiness zones except 11 and 12, and they prefer soil which is, like Auntie, a bit acidic. Unfortunately, the tap water used to irrigate houseplants is often harder than her heart, with a pH higher than 7.0, and can raise the pH of the soil as well. For plants that have begun to pale and pout, with brown-edged leaves and grudgingly slow growth, add about 1/4 teaspoon of vinegar to each gallon of water every time you water them.
Laving the Leaves
If you plan to show your African violet plants or just want them to look their well-scrubbed best for Auntie’s next visit, you can clean their fuzzy leaves with a natural sponge. First, thoroughly mix 1/2 teaspoon of vinegar and 2 teaspoons of Neem oil into 1 gallon of warm water. After you dip your sponge in the solution, squeeze out any excess liquid, so the sponge is barely damp when you dab the leaves with it. Allow the plants to dry before you return them to their regular position on a windowsill or under grow lights.
Purging the Pots
The common white buildup of calcium or fertilizer salts on the rims of flower pots is especially hard on African violets, as their horizontal leaves tend to rest on top of those rims. That encrustation can be as irritating as Auntie’s carping and will eventually kill the leaves contracting it. To clean your pots, remove the plants and soil first. Then dunk those pots in a bucket that contains two parts of water to one part of vinegar. Leave them to soak for an hour, and the gunk should loosen enough that it can be removed with a scrub brush.
Nullifying the Gnats
The constant watering required to keep the violets’ soil damp can eventually cause a buildup of fungus gnats in that soil. Like Auntie, those annoying fruit-fly-like insects may seem to have taken up permanent residence. However, you can rid yourself of them by filling an empty baby-food jar almost to its rim with water. If you add 1 tablespoon of vinegar to that water and position the open jar beside your plants, the bothersome bugs should obligingly drown themselves.