How to Fertilize Your Jungle Jack's Plumeria
There isn’t a whole lot of mystery when it comes to fertilizing plumeria, but there are
some myths and misconceptions. For example, many sites recommend a high phosphorus percentage (that’s the middle number in the N-P-K formula) for better blooming. This is not true or even essential, and while additional phosphorus will enhance bloom quality; it will not make the plant bloom. In fact, too much phosphorus is detrimental. (Unfortunately, even our own tags make this recommendation: that text was written early in our plumeria experience and we updated it in our next tag order.)
Don’t get obsessed over fertilizer ratios. A 3-1-2, 1-1-1, 2-1-2, etc. is fine for most of the growing season. One piece of advice though, when fertilizing early in the season use a lower nitrogen number, as the plant is not active yet and won’t need that much nitrogen. We use a 6-20-20 for our early season fertilizing.
If you have only small plants or just a few, regardless of container size, just plain old MiracleGro works just fine. I’m not getting paid by Scotts to make this endorsement (I wish!!!), but it’s simple to use and effective, and if you follow the directions, it’s impossible to burn your plants. We use MiracleGro on all of our 1 gal and 8” plants.
If you have a lot of plants, or plants in the ground, a 15-15-15 works well. A fertilizer with micro-nutrients, such as fish emulsion or seaweed extract, is good but not absolutely necessary. When applying fertilizer in a broadcast manner, take care not to overdo it, as too much nitrogen will cause burn. The best rule is use less fertilizer more often, as opposed to using more fertilizer less often.
My general recommendation is to fertilize about once a month or every 6 weeks during the growing season, depending on the type and amount of fertilizer being applied. If you’re using MiracleGro, once a month is good; with granular fertilizers about every 6 weeks is more advisable. There’s little to no point in fertilizing before April or after September when plumeria are dormant.
And no, to the best of our knowledge, there’s no magic formula that will force a plumeria to bloom. If you have one, I’m all ears.
If all this sounds simple, that’s because it is!