Growing Plants

When To Put Ferns Outside – Complete Instruction

When to put ferns outside? Ferns can offer a tropical ambiance to any garden. However, people don’t have much information about Boston fern care outside.

If you want to add ferns to your landscaping decor, learn when to put them outside with this guide.

Discover what ferns are, if they can go outside, and when to plant them outdoors. You’ll also learn about the types of outdoor ferns available and how to care for them properly.

What Are Ferns?

when to put ferns outside

Ferns are a popular type of non-flowering plant. It is known for its delicate, feathery fronds. The Boston fern is a species of fern that has been cultivated both outdoors and indoors for decades.

This sturdy plant, with sword-shaped fronds, is frequently used as a decorative shrub. People can grow them in pedestal planters, hanging baskets, and shaded garden settings.

Boston ferns flourish in damp, wooded regions requiring high humidity. Continuous wetness of the growing conditions both outdoors and indoors is favorable.

If properly planted, Boston ferns could provide long, arching stems of gorgeous foliage.

Can Ferns Go Outside?

Some fern varieties can be grown outside. However, you need to pay attention to the growing environment. Boston ferns, vulnerable to heat and cold, require a consistent temperature to flourish.

These tropical plants thrive in partially sunny outside. The locations should be away from direct sunshine indoors. Plus, they cannot survive cold weather.

Their favorable daytime temperatures are approximately 65 degrees Fahrenheit.

Meanwhile, the nighttime temperatures should not go below 55 degrees Fahrenheit.

Boston ferns must be taken indoors if night temperatures fall below 45 degrees. High temperatures can also harm Boston ferns. They will prosper when daytime temperatures do not exceed 75 degrees.

When Can You Put Ferns Outside? 

When to put ferns outside depends on many factors, including locations and types of ferns. However, one of the general rules is to consider your growth zone’s typical last frost date.

It is crucial when deciding whether to plant ferns outside.

For example, to lessen the chance of frost in Pennsylvania, the optimum time to grow ferns is Mother’s Day. It is around the second Sunday in May.

Furthermore, this period allows ferns to develop full size for a stunning show. Ferns can be placed sooner than Mother’s Day when you use a greenhouse. It could be in early spring cold temperatures.

If you decide to plant your Boston fern outdoors, the ideal time is spring or fall. You should choose a location with moist, well-draining soil and plenty of shade.

Besides, adding mulch around the plant base can keep the soil moist and in a more humid environment.

What Are Types Of Ferns That Can Go Outside? 

can ferns go outside

There are several types of ferns that can thrive outside. Some examples are Christmas fern, Boston fern, Lady fern, and some other varieties.

These ferns require moist, well-draining soil and plenty of shade. With proper care, these ferns can add a lush, tropical feel to your outdoor garden.

Christmas Fern

Polystichum acrostichoides, known as Christmas fern, is a common green fern. It features dark-colored fronds. The plants can grow very long, up to three feet long.

It gets its name from its similarity to pine-needle leaves. One of the benefits of Christmas fern is that it requires little care and may flourish in a range of situations.

However, it grows best in full or moderate shade. 

Boston Fern

Boston ferns, also known as Nephrolepis exaltata or sword ferns, are evergreen perennials. Their arching branches make them ideal for hanging baskets.

They may be planted both outdoors and indoors. However, they prefer a cool climate with partial shade. This living condition will help avoid scorching their fronds.

Tiger Fern and Lemon Buttons are excellent Boston fern outdoor garden varieties.

Lady Fern

The Lady Fern is easy to care for as they tolerate warm weather. It features brilliant green leaves with frond stems in red, purple, and green colors.

The plants may grow up to five feet tall. Although it favors wet soil, it may turn drought-tolerant when mature.

Its sprouting fronds and rhizomes are deadly when eaten uncooked.

Thus, it is not good when you raise pets. The Japanese-painted fern, Lady in Red, and ostrich fern are all excellent varieties for outdoor gardening.

Maidenhair Fern

Maidenhair ferns have delicate, brilliant green fronds with black stripes. The plants enjoy a humid environment and wet soil. They are susceptible to direct sunlight.

When you put them outside, you must place the trees only in full shade. American, southern, and northern maidenhair ferns are all acceptable for outdoor cultivation.

Osmunda Fern

Osmunda ferns are one of the longest fern species for backyard gardens. The plants will thrive in wet, gloomy, swampy environments like Missouri’s Ozark region.

Interrupted fern and Cinnamon fern are excellent choices for outdoor cultivation.

Wood Fern

The wood fern is a hardy plant that can survive a wide range of light conditions. It can withstand complete shade or indirect light.

This medium-sized fern type is particularly drought-tolerant once matured. 

It is an excellent choice for new fern gardeners. Leatherleaf fern, autumn fern, and marginal wood fern are all good choices for outdoor gardening.

How To Care For A Boston Fern Outside Properly?

Some ferns prefer cool temperatures and partial to full shade when planted outside. They can be planted in various locations, including hanging baskets or containers.

Some can tolerate the warm weather. However, most will thrive in well-drained and consistently moist conditions.

Ferns Temperature Outside 

Ferns planted as houseplants require bright and indirect light. The spot location should be changed frequently to ensure equal growth.

Excessive shadow produces drab, sparse fronds. Meanwhile, too much light causes fronds to be scorched.

Provide shade from harsh sunlight and high winds while cultivating Boston ferns outside. Containers having ferns have to be taken indoors throughout the cooler months.

Spread a two-inch layer of mulch over the soil. Organic mulch, such as leaf mold or pine bark, can hold moisture and keep the temperature suitable.

Planting Locations

Choose a shaded site to grow ferns since most ferns like partial to full shade. Provide additional water to make up for the heat even when the kind of plant can endure the partial sun.

Put ferns in damp, moderately acidic soil (pH of 5 to 5.5). It is because they thrive in humid woods and close to water sources in the wild.

Remember, even drought-tolerant fern cultivars often require damp soil when planted.

Planting Methods

Boston ferns will flourish from water-soluble fertilizer after 4 to 6 weeks in summer and spring. Don’t apply fertilizers in winter or fall.

If the fern sheds many leaves, prune it to 2 inches in springtime. When planting, select a pot large enough to allow for development.

However, the pot should not be so large either, as the plant spends energy developing roots rather than foliage.

Plus, as the soil holds excessive moisture, a too-large container might cause rot in the roots.

Frequently Asked Questions

boston fern care outside

Can A Boston Fern Live Outside?

Yes, but you need to prepare for good growing conditions. Boston ferns can develop outside in hardiness zones 9 to 11, although they require a lot of water.

Choose a position in partial or full shade with shelter against drying winds in these zones.

Potted ferns may be cultivated outside of these zones. However, they must be taken indoors once temperatures fall around 45 degrees Fahrenheit.

What Are Boston Fern Light Requirements Outside?

Water ferns regularly to maintain the top five inches of soil wet. Remember to avoid overwatering. Provide more water as needed during the growing season.

Though many ferns do not need fertilizer, a slow-release fertilizer applied in the spring might encourage new growth.

Pests like slugs can harm fern fronds, so keep an eye out for them. To keep slugs away, build a barrier out of diatomaceous earth or crushed eggshells.

How Long Can Ferns Stay Outside? 

The length of time ferns can stay outside depends on several factors. Some essential ones include the specific species, climate conditions, and location.

Some ferns, such as the southern maidenhair and cinnamon fern, can tolerate colder temperatures. They may be able to stay outside year-round in certain regions.

However, most ferns are sensitive to frost and freezing temperatures. They will not withstand when temperatures drop below 45 degrees Fahrenheit.

According to the University of Georgia, a sudden decrease in nighttime temperatures can harm the foliage of ferns.


If you’re wondering when to put ferns outside, it’s important to consider the specific species and climate conditions. Most ferns are sensitive to freezing temperatures.

For proper Boston fern care outdoors, choose a shady location, use well-draining soil, and provide consistent moisture.

Remember to move ferns indoors when temperatures drop below 45 degrees Fahrenheit.

Samuel Mark

Hello I am Samuel. Samuel's Garden is a garden blog where I share my experiences in garden caring and tree growth. Hope you enjoy it!

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