This healthy looking, well-fed Green Island Ficus (Ficus microcarpa ‘Green Island’), by Alan Kieffer, originally appeared in Bonsai Today issue 74, in an article by Mary Miller.
A fertilizing program we like
The following program is one that I like. Feel free to adjust, elaborate, or simplify according to you needs and preferences.
Start with pellets in the very late winter
Apply about one third the recommended dosage* of Green Dream or other pellet or chunky natural fertilizer in the very late winter (just before the buds begin to swell).
Starting about three weeks after your first application, apply the about half the recommended dosage* every three weeks until mid-summer, and then gradually reduce the number of pellets you apply, so that by mid fall (when leaves are turning and falling where you live) you are applying only about 10% of the of earlier dosage.
You don’t have to be fanatical about the timing; the point is to feed less and less from mid-summer to mid-fall, and then stop altogether by the time leaves have fallen where you live. If you are concerned about feeding so late, you can stop earlier, though very small amounts of very mild slow-release pellets will enrich the soil just enough, but not too much, for the coming winter and early spring.
Next introduce a liquid
Use the manufacturer’s recommended dosage of Dyna-gro 7-9-5 (or another fairly mild liquid with a balanced N-P-K) every other week from early spring until late-mid summer (that’s mid to late July here in northern Vermont).
Add fish (or fish/seaweed)
On alternate weeks, use the manufacturer’s recommended dosage of Neptune’s Harvest fish/seaweed, or some other similar fish product. (If you live where raccoons or other critters are a problem, you might want to skip the fish.) From mid-summer until early fall gradually reduce the dosage by weakening the solution (more water, less fish). Your last feeding should be no later than early fall and should be quite weak.
Seaweed as a tonic
Some people (including me) like to use liquid seaweed as a tonic. The best time to do this is mid to late winter (about a month before you start the pellets) and late fall/early winter, or month or two after you have stopped feeding.
*Recommend dosages
Labels on pellet type fertilizers often suggest that you apply the recommended dosage every 6 weeks, or (in the case of Green King) two months , or something like that. I prefer adding smaller amounts about every three weeks. I think this assures a steadier (more even) supply of nutrients.
Other feeding programs
There are almost as many feeding programs as there are bonsai growers, and you can certainly experiment to find programs that suit your needs.
Super Feeding
One very intense program that some people like is called ‘Super Feeding.’ It was devised by Michael Persiano and can be found in our Pine book. It isn’t suitable for everyone and all types trees in all conditions, but, some people who are looking for rapid, balanced growth, swear by it.