Every Bonsai needs the right amount of light to grow strong and healthy, and direct sunlight is often the best source. But too much of a good thing can cause damage, so it’s important to understand how to control your Bonsai’s exposure.
To get started, it helps to know that sun-exposure requirements vary based on species and season. When deciding where to place your tree, take into consideration its natural environment – a tropical tree should receive 5 hours of direct sunlight in summer, while conifers may need up to 6 hours year-round.
Fluctuating temperatures from heat and sun can shock your plant, so gradually adjust your Bonsai as if bringing it outside for a picnic—start with one hour for the first few days and then increase by 30 minutes each week until you hit the suggested time limit.
Also, consider shading devices like window screens or slatted structures you can build or buy at a nursery, which will filter out damaging UV rays while allowing enough light to see through during cloudy days. Remember to check your tree daily for signs of sunburn (seared leaves) or stress (flagging colors) and take steps immediately if needed.
Finally, be sure to give water when necessary – especially during hot summer months – as bonsais are extremely sensitive thirst-wise due to their shallow root systems.
Essentially careful management of direct sunlight is key for any healthy bonsai specimen — just don’t forget the sunscreen!