When watering bonsai, the aim is to water in the Goldilocks zone – not too wet, not too dry. Compare watering bonsai it to baking a cake. Your goal shouldn’t be to take a cake out of the oven before its cooked because you’re worried about overcooking it. If you take a cake out of the oven too early because you don’t want to burn it, you’re not going to get a good result.
Watering bonsai is similar, your goal shouldn’t be to water the bonsai before it is ready because your worried about it becoming too dry. If you continually water your bonsai too frequently, you’re not going to get a good result. With time and experience, you will get to know the correct timing to achieve the best result. Your frequency of watering will be different to other’s because of local conditions. Not all ovens cook the same. You should be aiming to water a bonsai only when its ready to be watered.
To tell if the bonsai is ready to be watered:
- The top soil should be dry
- Use a wooden chopstick to stick into the soil and see if it comes out dry, slightly moist or wet. If its dry or very slightly moist you can water.
- Feel the weight of the bonsai. Get used to the weight of each bonsai, pick up tree and if it is heavy there is water in it, if it is light then tree is dry
- Any bonsai that has soil more than slightly moist should be left alone. The only exception to this is if it is going to be a hot day and you are pre-watering because you can’t water later. This should only be done occasionally in summer.
The bottom line is each and every bonsai should be checked twice a day to assess soil moisture and water requirements. This takes time, patients and experience.
One way to learn about how much water the soil is holding is to use a wooden chopstick.
Here is a video demonstration how I do it.