Hostas, commonly known for thriving in shady areas, do have several types that can withstand direct sunlight for a few hours daily. However, in regions with intense sun exposure, like the southern states, these sun-tolerant hostas may still suffer from sunburn and drought damage.
To ensure their health, it’s crucial to water these plants thoroughly and regularly, maintaining a consistently moist soil environment. Additionally, applying a layer of mulch—such as shredded leaves or evergreen needles—around the plants helps in keeping the soil cool and moisture levels stable.
Next, I will delve deeper into the steps required to both remedy sunburn in hostas and prevent it from occurring.
1. Give enough water
When you spot signs of scorching on your hosta leaves, the initial step is to ensure the plant is adequately hydrated.
Thoroughly water the soil, taking care to avoid creating swamp-like conditions. Depending on your hosta’s size, use about 1-2 gallons of water.
It’s best to water in the evening, avoiding the hotter parts of the day, which can be detrimental.
In the future, maintain a balance in the soil moisture – it should never dry out more than an inch deep. Aim for a consistently moist, but not overly saturated, soil condition.
2. Provide more shade
Leaf scorch in hostas is primarily caused by too much direct sunlight. While some varieties can handle a few hours of sun, the intensity varies by region. For instance, the sun in Hardiness zones 7-8 is stronger than in zones 3 or 4, affecting hostas differently even with the same sunlight exposure.
To protect your hostas, increase the shade they receive. If natural shade is limited, consider using shade netting available at most garden centers. Choose netting that blocks at least 50% of sunlight.
Create a simple frame using four stakes placed around the hosta, and drape the netting over it. This temporary shade can be removed at season’s end when the hosta leaves die back and the plant enters dormancy.
Read more: Hosta Light Requirements
3. Transplant hosta
The previous tips are effective as short-term fixes, but if your hostas persistently suffer from scorch, relocating them to a fully shaded area is advisable. Let’s delve into the proper way to transplant hostas.
The ideal times for transplantation are mid-spring or early fall, offering the most favorable conditions for relocation. Ensure this is done at least 35-40 days before the expected first frost.
Choose a new spot that either offers full shade or receives mild morning sunlight for about 2-3 hours at most.
When digging up the hosta, handle the root ball with care to avoid damaging the plant. At the new site, prepare a hole twice as wide as the hosta’s rhizome. Mix garden soil with high-quality compost for filling.
Initially, fill the hole halfway with this mixture. Position the hosta ensuring its stems are above soil level, maintaining the same growth level as before.
After placing the plant, fill any gaps with soil and lightly water. The soil will settle after the water seeps through. Add more soil to level it off and water again to ensure proper settling.
Read also: How and when it is best to transplant hostas.
4. Do not cut off burned leaves
Avoid trimming off scorched leaves in most situations, as they can still contribute positively to the plant’s growth. Scorched leaves typically show damage only at their tips and edges, often affecting less than 10-15% of the leaf. In such cases, it’s unnecessary to cut them.
Even with partial damage, these leaves continue to photosynthesize throughout the growing season, providing essential energy for the hosta’s growth.
However, if more than three-quarters of a leaf is burnt, it becomes susceptible to diseases, especially in damp conditions. To prevent these issues, it’s advisable to completely remove leaves that are extensively damaged.
5. Plant sun-tolerant hostas
Consider planting hostas that are more tolerant to sunlight. Varieties like Sum and Substance, Gold Standard, Sundance, Sun Power, and others are known for their sun resilience.
However, sun tolerance doesn’t mean these hostas can withstand excessive exposure. Avoid placing them in areas where they’ll receive more than 4-5 hours of direct sunlight, particularly during the intense midday period. In the northern U.S., they might handle up to 6 hours of sunlight.
In warmer climates, specifically hardiness zones 7 and 8, it’s generally not advisable to plant hostas in direct sunlight. While they may cope initially, harsh, dry summers can lead to leaf burn.
It’s especially important to avoid full sun for blue hostas. These varieties need deep shade to maintain their vibrant blue hue. Exposure to even a small amount of sun can cause their leaves to fade to a pale green.
Read more: Are there any hostas that can take full sun?
6. Mulch hostas
Applying mulch is an effective way to retain soil moisture, particularly beneficial for hostas. It helps prevent the soil surface from drying out too quickly.
Another significant benefit of mulching is temperature regulation. Mulch keeps the soil cooler, providing a more comfortable environment for the plants during hot summer days.
For hostas, compost or pine bark is ideal. Compost not only serves as a mulch but also enriches the soil with nutrients, further supporting the health of the hostas.
While these are preferred choices, there are numerous other mulching materials available. For more detailed information on these alternatives and guidance on proper mulching techniques for hostas, you might find my dedicated article on this topic very useful.