How not to fertilize…
Last year I wrote a post about fertilizing, Refine your fertilizing this year! I wanted to expand on that and offer a few more notes, since, after all, it’s a brand new year for dung related issues-
Blogging is really a bit assumption-ridden, because we make one simple statement as if it’s unconnected to a million variables. For example, when I say ‘fertilize’, I assume that we’re using a fertilizer that has all 6 macronutrients, Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), and Sulfur (S), which, if I don’t say that, or some other variable you’re assuming and I’m not, we’re NOWHERE. And we are better if we’re somewhere. At least.
- There are very few instances in bonsai, in early training or maintenance, where you don’t want a fertilizer with at least all 6 macronutrients. (i.e., without magnesium your tree can’t create chlorophyll, and without chlorophyll the idea that your plant can create food for itself is sort of unconnected to reality, and hence, bending a branch is cosmically silly-)
Ok, covered that variable.
A few fertilizing comments for this 2014 season:
- Many problems we might see—burned leaves, browning needle tips, leaves that are too dark green, etc.—are very often basic care issues that have nothing to do with fertilizing. Just to take that last one, very dark green leaves is an indication a bonsai that is not getting enough sun.
- There’s rarely a need to slam a tree with twice as much fertilizer as the directions suggest. More of enough is not better in the world of plant nutrition.
- Normally, flowering trees are first fertilized after the flowering period. But this is another general statement. Some plants are nearly perpetual bloomers, like the quince I’ve talked about so much here, Chojubai, and those should be first fertilized when they are growing shoots in the spring even though they might still be flowering.
- If we fertilize flowering accents randomly or broadcast, you may diminish the blooming of some. Fertilize them like your trees, when they finish blooming, not during.
- If we fertilize an old tree too much—a pine with craggy, old bark for instance—it may shed that old bark and begin looking young. Many plants are perennials in ways we cannot be, for they can be restored to youth quite literally.
- If we under-fertilize a young tree it will begin to look older than it is…for one thing, it will develop bark faster. But it may take much longer to achieve the other goals we seek in bonsai, too, like substantial trunks, etc.
- Get your water and soil tested! Fertilizing will be different for different pH ranges. For example, recent research suggests that phosphorus (P) from bone meal is only available to plants in soils with a pH below 7.0. In fact, for most bonsai, if you can get close to 6.5 pH, most plant nutrition problems are greatly minimized.
- Finally, fertilizing is much less important than optimizing the big ones: Sun and water. If we optimize the big ones, we won’t be turning to fertilizer as if it were a magic bullet. It isn’t one. It’s a distant second stage booster on our little rockets.
Are you yawning yet? Well, I know it’s not jazzy stuff. The world of bonsai has more exciting parts to it, and can get pretty romantic, too. Hybridizing with flowers, for instance, is a sure way to make at least a few people blush. But hopefully you’re yawning more interestedly now about fertilizing.
Fertilizing incredibly well is only for really cool people. Join the Smelly dorks! We’re a band of organic fertilizing rebels called the Secret Smelly Society, and we’re not growing very fast. Ironically.