Low-quality or substandard potting media is a major source of problems with plumeria grown in containers (and, really, any container-grown plants). Plumerias that are potted in substandard or old decomposed potting soil are weaker than healthy plants, so they’re more likely to drop leaves, turn yellow, attract pests, and just generally die.
Potting media, of course, is just one of the factors that contribute to healthy plumeria. But because most people only re-pot when they have too, it’s actually the hardest single factor to quickly control. Other factors that are much easier to control include moisture levels, pH, humidity, temperature, and light levels.
Because potting soil is so important and relatively hard to change, it’s extra important to pay careful attention to your potting media and start off with the best possible mix. Your plumeria will thank you for it, and ultimately, you’ll end up with healthier plumeria and more blooms.
A good potting media should:
- Provide support for the growing plant
- Provide adequate drainage, which is very important for Plumeria
- Provide adequate available nutrients (usually through a fertilizer and/or organic matter added to the soil)
- Provide adequate aeration around the roots
You can easily find many good potting mixes. Most are based on sphagnum peat moss, with additives like compost, humus, perlite, vermiculite, and pumice. Some have water-retention crystals, but these are not good for plumeria. You can also find soils with fertilizer added, pine bark, and other ingredients like coir, seaweed, and worm castings. I prefer to use a non fertilized soil mix, that way I know what I’m starting with.
For plumeria, it is important the soil you select allows for adequate drainage, it has air pockets around the root zone, and critically, how long does it last before the inevitable decay sets in (all organic things decay) and starts to lose its desirable qualities?