“I did know thee in the wilderness, in the land of great drought.” ― Hosea 13:5
California has been dry for the last four years. The lakes and reserviors are emptying. I went digging for California junipers recently near Lake Matthews, and the water level in the lake was shockingly low. Last summer, California water regulators approved daily fines up to $500 for wasting water. What can the bonsai enthusiast do to avoid using too much water? There are a few suggestions I've seen being passed around in some of the clubs:
- Change the soil mixture. When you repot, consider adding more bark, perlite, soil amendments and other organic elements to retain water in the soil. This will let you water those trees less frequently, although you will lose some of the benefits of an extremely porous soil if you use something like "Boon's mix."
- Hand water trees rather than relying on sprinklers and other automatic watering systems. As you water, skip trees that don't look like their soil needs water. If you use a hose, turn off the spray as you go from tree to tree or bench to bench.
- Use Cloud Cover or Wilt Pruf to reduce transpiration, especially when foliage returns in Spring.
- Recapture runoff and recycle the water. You can capture rainwater and divert it from gutters and into storage barrels, or just put some mixing tubs under your benches while watering, and pour the drainoff back into your watering can for the next bench.
- Reduce exposure to sun. Consider moving trees to locations that get less afternoon sun, or putting them under shade cloth. Cooler pots and soil need less water.
- Wrap pots (especially darker pots) with cloth or burlap to lower temperatures in the soil and reduce the need for water.
- Cover the soil with sphagnum moss, or use soil covers after watering to keep the soil moist longer.
- Remove trees from pedestals or high benches to reduce air circulation beneath the pot. You might get more spiders, slugs and bugs, but you'll use less water.
If you're still using too much water, consider donating some of your less favorite trees.
Or pray for an El Niño.