Rubber Plant Leaves Turning Red and Dropping

Question

We bought a rubber plant maybe 5 months ago. Looked like it was thriving inside the OSH store we bought it from. Probably not the best thing to do but we repotted it when we got home (Miracle Grow + extra perlite). It started dropping leaves but we figured it was just acclimating at first. After some time and some more leaves we brought it to a corner next to a window with more light (although not a whole lot due to the tree outside). Continued to not do great so we talked to someone at a nursery and they recommended a different soil - a cactus mix so that it could drain very well - as well as Dr Earth fertilizer.

After repotting with the cactus mix (no fertilizer yet) the rubber plant started to do better! No more dropping leaves and a new leaf started in two of the stalks.

It was good for about a month or two and then leaves started dropping again. Figured it was time to use the fertilizer so we did but no help. We've moved it to another window that gets more light where a Monstera has been doing well.

There are two new growths at the bottom (new stalks) that havent dropped and seem to be happy but the big ones are not.

Pictures are: the plant, one of the leaves on the plant that is turning red, a leaf that fell, and the stem of the leaf that fell.

Answer 1

Ficus elastica is a robust house plant. In the wild this plant can grow 130 feet tall but can be managed so it stays smaller in the home.

For most indoor plants the biggest stress factors are:

• too much water
• not enough light

Less common problems can be:

• pest problems coming with the plant from the grower
• high fertilizer levels at the grower combined with low light at home can cause elevated levels of salts (unused fertilizer) in the soil

There are a few things going on here that you can correct or diagnose:

• repotting a plant can be a stress. There is no need to repot this plant now for several years. When you do repot use a tropical potting soil.
• there is no need to add fertilizer when you repot a plant. Fertilize only when you see new growth and then use half or one quarter strength.
• check that the plant has enough light. It needs to be next to a window with an unobstructed view south, east or west in the Northern Hemisphere or north, east or west in the Southern Hemisphere. Blinds should be up and drapes should be pulled back. If the plant does not get enough light it will drop leaves
• water the plant thoroughly so wager runs out the bottom of the pot when the top inch of soil is dry. This could be every other week.
• check the underside of the leaves for spider mites which look like grains of salt. There might be webbing which means they are well established. Control with a cloth soaked in soap and water. Wipe all the leaves top and bottom, rinse the soap off and repeat every five or six days. Treat at least three times to get the eggs which hatch later.