Fertilizing Your Bonsai

Healthy bonsai require regular fertilization because they grow in a small amount of soil (inorganic) and quickly use available nutrients. At Bonsai Learning Center, we recommend a two-step fertilization program during the growing season (approximately March through September where we are North Carolina). This instructional guide is for bonsai in pots.

Step 1: Organic Fertilizer Cakes

Apply organic fertilizer cakes on the soil surface using fertilizer cups.

The fertilizer cups allow water and rain to carry nutrients into the soil while preventing the organic fertilizer from breaking apart and clogging the soil matrix.

Recommended Products:

• BioGold Original Bonsai Fertilizer
• Fertilizer Cups

Instructions:

1. Place fertilizer cups on the soil surface.
2. Fill cups with organic fertilizer cakes.
3. Water normally.
4. Every 4 to 5 weeks, remove and discard the old fertilizer.
5. Replace with fresh fertilizer cakes.

The nitrogen in organic fertilizer is largely depleted after about 4 to 5 weeks, so regular replacement is important.

Step 2: Liquid Fertilizer Program

In addition to the organic fertilizer cakes, apply liquid fertilizer every two weeks.

Recommended Products:

• Bonsai Pro 7-9-5
• Fish Emulsion/Kelp Supplement
• MicroTotal Foliar Fertilizer

Suggested Schedule:

• Week 1: Bonsai Pro
• Week 3: Fish Emulsion/Kelp
• Week 5: Bonsai Pro
• Week 7: Fish Emulsion/Kelp

Continue alternating throughout the growing season.

MicroTotal can be added to your Bonsai Pro application once per month to provide essential micronutrients.

Fall and Winter Fertilization

From approximately October through December, switch to a low-nitrogen fertilizer.

Recommended Product:

• Ho Yoku 0-10-10 Nitrogen-Free Fertilizer

This fertilizer promotes strong root development and winter hardiness without encouraging tender new growth. New growth produced late in the season is vulnerable to damage from freezing temperatures, so we avoid fertilizers containing nitrogen during this period.

Important Notes

• Fertilize only healthy, actively growing trees.
• Discontinue fertilization on dormant trees during winter.
• Tropical bonsai growing indoors may continue to receive light fertilization year-round.