Bonsai soil is designed to drain water away quickly, carrying with it the vital nutrients your Bonsai tree needs.

How often should I fertilize my bonsai tree?

So fertilizing your Bonsai tree is important and should be done regularly during the growing season. Every two weeks is a good rule of thumb.

What is the difference between liquid and granular (pelletized) fertilizers?

Liquid fertilizer is quick acting and easy to use; just add it to your watering can when you water. But it also dissipates quicker than granular fertilizers do by leaching out with the water. Granular fertilizers are usually just pushed into the soil surface of your plant and dissolve as you water normally. They're easy to use but can be unsightly and some smell a little funky.

Related Fertilizing Articles:

> Bonsai Fertilizing - The Basics

> How to Choose Bonsai Fertilizer

> Why You Must Fertilize Your Bonsai Tree

> Bonsai Fertilizer Frequently Asked Questions

What does it mean when it says a fertilizer is organic?

Fertilizers are made two ways: organically and synthetically. Organic fertilizers are made from natural sources - everything from fish to chicken poop is used. Synthetic fertilizers are formulated chemically. Which one is better is a matter of debate, but the bottom line is your tree can't tell the difference between the two, and won't care. 

What is the difference between a fertilizer and a Vitamin?

Fertilizers provide nitrogen, phosphorus and potassium (among other things) that promote the vigorous growth and health of your Bonsai tree. Vitamins on the other hand, are formulated to enhance the condition of the soil, stimulate the root system and encourage macrobiotic growth. It’s a little like giving your Bonsai a multivitamin to supplement your tree’s normal diet of fertilizer. Vitamins also help your tree fight off diseases and allows them to better handle pruning and re-potting.

What does a fertilizer’s NPK ratio mean?

Fertilizers are assigned three numbers that represent the proportion of Nitrogen, Phosphorus and Potassium, in that order. A 3-1-2 fertilizer would be 3% Nitrogen, 1% Phosphorus and 2% Potassium (leaving 94% of inert ingredients.) A 5-5-5 fertilizer would have the same proportion of all three and is called a balanced fertilizer.

Remember the numbers this way: Up, down and all around. Up = Nitrogen that promotes foliage growth. Down = Phosphorus that promotes healthy roots and All around = Potassium that benefits the whole plant.

  • Nitrogen
    Digging further, you will see that nitrogen is composed of Nitrate Nitrogen, Ammoniacal Nitrogen and/or Urea. Nitrate Nitrogen is readily available to a plant. Ammoniacal Nitrogen is the second element to be taken up, but at a slower rate, and finally Urea. Urea, however, is not soluble in water so in a hydroponic system it is almost useless.

  • Phosphorus
    Next, phosphorus is generally considered important for early root development and for increased flower bud set and color. Fertilizers with low phosphorus ratios will produce short and bushy plants. Too little phosphorus and stunting will occur.

  • Potassium
    Lastly, potassium plays a major factor in plant respiration and water uptake. High potassium promotes sturdy, solid stem and leaf development. For instance a finishing fertilizer may have high potassium to harden growth and increase stem length of a flower.

Can I use the fertilizer and vitamins together?

Yep, just mix them in the same amount of water you normally would and they can be used side by side.

How long will fertilizer or vitamins that I have mixed in a jug stay good?

You can mix up your fertilizer in advance and keep it in a cool place out of the sun and it should be good for a few weeks. After that the nutrients begin to break down. Make sure you shake the container well before using.

Do I need to fertilize in the winter?

Yes indeed. Although your tree will be dormant and additional nitrogen isn’t needed, the rest of the plant will benefit plenty from a no-nitrogen fertilizer. Your bonsai will stay happy and healthy during the dormant months and more vigorous in the Spring. 

Fertilizer Usage Amounts

  • Bio Gold: Use every 6 to 7 weeks during the growing season at a rate of 12 -15 pellets in a 6” pot, and 30 – 40 pellets in a 12” pot. Press into the soil surface and water.

  • Organic Pelletized Fertilizer: Use monthly during the growing season at a rate of ½ teaspoon in a 4” pot; ¾ teaspoon in a 6” pot; ½ tablespoon in a 12” pot. Press into the soil surface and water 

  • Liquid Fertilizer:* Apply every two weeks during the growing season. Mix 1 tablespoon per gallon or 1 1/3 teaspoon per quart and water as usual.

  • Liquid Vitamins:* Apply every two weeks. Mix 1 teaspoon per gallon and water as us usual.

  • Hi-Nitrogen Summer Fertilizer: Apply once a week during the growing season. Mix teaspoon per quart and water as usual.

  • No-Nitrogen Fertilizer: Apply once a week during the dormant/winter season. Mix 2 teaspoon per gallon and water as usual.

*These two products can be mixed and used at the same time at their normal dilution rate.


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