Q: We have camellias that are about 50 years old. Can your gardeners give us some ways to conserve indoor water and grey water to water them? They like acid, so water that contains soap and is therefore basic (alkali) would need to be neutralized; can it be done, and if so how? Adding vinegar? How much? Should the plants be pruned severely? Are there particular mulches that would be more suitable than others? We would welcome advice about camellia care in droughts as severe as this one is. – Linda Johnson, Granite Bay
A: The good news: Camellias are pretty tough. Your shrubs already have survived droughts, just not one quite this bad.
Camellias, a favorite flower in Sacramento, have quite a bit of natural drought tolerance. Sacramento earned its “Camellia City” nickname because of the many bushes in this area that date back to the 1920s or earlier. Camellias adapt well to our climate, including its dry spells.
To reach their advanced age, your plants have developed deep roots that can reach moisture a foot or more below the surface. That will help during this crisis.
Camellias need the most water during bloom stage, which is right now. Recent rain helped them out there.
Start irrigating them in March on a once-a-week, plant-by-plant basis. If planted in the ground, a large shrub needs 1 to 2 gallons of water a week. You can catch that much in a bucket while waiting for your shower to warm up in the morning.
Camellias don’t like grey water; that’s water that’s been used for laundry, baths or dish washing. It usually contains soap, which can build up in the soil. As you noted, camellias prefer acidic soil. Along with azaleas and rhododendrons, camellias can’t deal with soap build-up. Adding vinegar won’t balance out the pH.
Instead of grey water, look for other water sources, such as the shower bucket. Another possibility: Save cooking water such as that used for boiling pasta or steaming vegetables. Skip the salt and let the water cool thoroughly before using on plants. Again, all you need is a gallon (or two) per week per plant.
Don’t prune your camellias. They need little if any pruning during normal water years. Pruning prompts them to grow more, which requires more (not less) water. And pruning causes plants stress; they’re already under drought stress and don’t need any more.
Mulch can help retain moisture around camellias but use it sparingly. A layer 1-inch thick is plenty for camellias; don’t let it mound around the trunk. Camellias prefer organic mulches such as bark and wood chips. Pine needles (which are very acidic) work well, too. Avoid rock mulch; that heats up the soil and may cause roots to suffer.