I grow African violets; some produce great blooms for me while others refuse to do so.. How can I make them flower?
Also, I have one plant where the bottom leaves died off and the stem is now approximately 5 inches tall with no leaves on the bottom only on top. The stem looks like it has “thorns” where the leaves dropped off from. What could cause this ??
First, let’s talk about blooming. Hard to say why one blooms and not the other. Violets tend to bloom when slightly pot bound. They need bright indirect light (East window) throughout the year and temperatures ranging from 60-80 degrees. In order to flower, violets should receive no more than 16 hrs of light/day. Saintpaulias will grow with as little as 3 hrs of light per day. Conversely, they need at least 8 hrs of darkness to trigger bloom.
The soilless mix that they are planted in have little nutrients and need to be supplemented, therefore feed it with a balanced liquid fertilizer (20-20-20) at 1/4 strength every time you water. Avoid fertilizer with urea which can cause root burn, pale leaves and reduce blooming.
Another old suggestion is to sprinkle epson salts (magnesium sulfate) on top of the soil and water it in. Apply it once. It may take a month to see any results.
Bare neck syndrome
When the lower leaves die back, they produce a “bare neck” look; to remedy this take the dull end of a knife and scape off the dead tissue along the stem, then repot so that the leaves line up with the edge of the pot and fill with soil.