Keep Ferns Lush in August: 5 Simple Care Tips

According to Gardening Know How, ferns can struggle in the heat of late summer. The article offers five simple tasks to keep them lush and prevent browning and crisping.

Watering

Ferns need moisture, especially when the sun is strong. Check the soil of every outdoor fern daily in August. Insert a finger a few inches deep; if it feels dry, water immediately. Morning watering is best. For container ferns, water until it runs out the drainage hole. Bottom watering is also recommended. A simple soil moisture meter can help keep track of moisture levels.

If the soil is dry, fern leaves will wilt or turn brown. Dry or brittle leaves mean the soil has been dry for more than a minute.

Misting

Misting cleans dust from fronds and adds humidity. Use a fine spray bottle with filtered or distilled water to avoid mineral spots. Mist indoor and outdoor fronds every day during August heat. Place fern containers on a pebble tray filled with water to maintain high moisture. Never mist fern leaves if the plant is in full sun. Indoors, a humidifier can also help.

Shade

Container ferns should not spend the heat of the day in full sun. Even indoors, hot sun rays can scorch fronds. Bed-planted ferns should avoid direct summer sun. If you planted them in a sunny spot, add an outdoor shade cloth to reduce heat. A fast-growing shade tree can provide protection in future years.

Mulch and Feeding

Mulch cools soil and traps water. Spread a thin layer of organic compost or chopped leaves over fern soil. Do not pile mulch against the center of the plant; leave space around the fronds to prevent rot. Mulch also blocks weeds.

In August, trim yellow or brown fronds at the base to encourage new growth and improve airflow. If you have been giving ferns a light monthly fertilization, you can continue. Use a weak, diluted liquid fertilizer, not too much. Avoid heavy fertilization during August, as extreme heatwaves can stress the plant.

Use a balanced feed 1:1 with water and pour into potted ferns for a boost of nutrition.

For more detailed fern care statistics, see the stats page. If you want to compare different fern species, look at the squad list.

Expert Insight

Teo Spengler is a master gardener and a docent at the San Francisco Botanical Garden, where she hosts public tours. She has studied horticulture and written about nature, trees, plants and gardening for more than two decades. Before turning her focus to gardening, she worked as an attorney and legal writer, experience she also brings to her role as our Gardening Lawyer. Her extended family includes some 30 houseplants and hundreds of outdoor plants, including 250 trees, which are her main passion. Spengler currently splits her life between San Francisco and the French Basque Country, though she was raised in Alaska, giving her experience of gardening in a range of climates.

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