Think you have fungus on your hosta?
Consider another possible diagnosis based on the plants’ exposure to sun. Although some can tolerate more sun than others, hostas are basically known as shade loving plants. Their vascular systems tend to only be able to handle a lower level of transpiration.
Transpiration is the transfer of water from the roots, through the plant’s vascular system to tiny pores underneath its leaves where it changes to vapor and is released into the air.
Non-sun tolerant hostas when put in sunny conditions are being asked to replace water at a rate that their vascular system cannot handle. Hence sunburn.
Here are a few tips about using hosta in sunny conditions.
- Use varieties with light green to green leaves. August Moon and Guacamole are good examples.
- Stay away from using variegated hosta.
- Never use hosta in a sunny spot unless it is irrigated or you are prepared to water it by hand…a lot.
This is what sun burned hosta can look like