Chapter 63 Housekeeping Tips and Tricks

63.1 Cleaning Lime Scale Off Pots

Over time, minerals in your water can accumulate on pots as white lime scale. This can be removed easily from pots when they are empty.

  1. Put 3-4 Tablespoons of Vinegar in 1 gallon of Water.
  2. Soak pots overnight.
  3. Scrub pots with stiff brush the next day.

If you have scale on pots that still contain trees, mix the commercial product CLR (for Calcium, Lime, and Rust) Cleaner, and wipe the OUTSIDE of the pot. DO NOT let CLR get inside the pot. It is toxic to roots.

63.2 Making Homemade Organic Bonsai Fertilizer Cakes

Personally I prefer to apply a slow-release fertilizer as a top-dressing, but many stylists like to use a purely organic fertilizer like this one. The basic recipe can be adjusted to provide different N-P-K ratios.

Wear rubber gloves when mixing this recipe. It can be very irritating to your skin.

  1. Mix these dry ingredients in a plastic tray or dish pan.
    • 3 parts Michigan reed-sedge peat, screened through fine mesh
      • This is strictly for a binder; it provides no nutrients
    • 1 part bone meal (avg. N = 4.0%, P = 12%, K = 0%)
      • Diluted 1:6, final contribution is 0.7% N, 2% P
    • 1 part cotton seed meal (avg. N = 5%, P = 2.0%, K = 1.0%)
      • Diluted 1:6, final contribution is 0.8% N, 0.7% P, 0.15% K
    • 1 part blood meal (avg. N = 13%, P = 1.0%, K = 0.6%).
      • Diluted 1:6, final contribution is 2.1% N, 0.7% P, 0.1% K
  2. Add enough water to bind into a thick paste consistency.
  3. Roll into 1.5” diameter individual balls immediately.
  4. Dry in the sun for 1-3 days.

Do not store the cakes; put 1-3 on top of the soil oe each pot shortly after making them. Do not place them atop your moss; they will kill most moss. The balls will feed slowly for 30-60 days depending upon how frequently you water. The depleted husk can be discarded after it is used up.

The final mixture is approximately 3.6% N, 3.4% P, 0.25% K. The potassium can be raised by adding 1 part of greensand (avg. N/P/K = 0/0/0.5).

Adding micro-nutrients to the dry ingredients can make them into a more well-rounded mix too.

63.3 Protecting Small Pots in Summer

Mame and shohin sized trees can suffer in our summer heat. To keep these small pots cooler, punch drainage holes in a large dishpan, sweater box or other plastic tray, then fill it with 3-4 inches of sand. Bury all the pots to their rims in the sand, then water both the pots and the sand. The sand insulates the roots and pots from temperature extremes, cools them by evaporation, and provides extra moisture from below.

Two dwarf hinoki cypresses being planted in a sandbox. One pot has already been sunk in sand. The other tree still sits atop the sand. Original photo by Dan Johnson.

Both hinoki cypresses have been sunk in the sand. This extra protection lets me put the pots in a sunnier location so they can fill out gaps in the foliage. Original photo by Dan Johnson.