Lemon button fern, Nephrolepsis cordifolia ‘Duffii’ is a relation of Boston fern. It also has numerous other common names including button sword fern, little-leaved sword fern, erect sword fern… and more.
Small, compact, and easy to grow, this fern is a great option for those who are not necessarily the most green-fingered with their houseplants. A faint lemon fragrance emitted by the foliage of this fern also makes it a pleasing option to grow indoors.
What is Lemon Button Fern?
Of the same genus as the ubiquitous Boston fern, lemon button ferns look similar to their relatives, but remain smaller and more compact. The lemon scent of the leaves also sets this cultivar apart. The foliage is a mid-green, with fronds of a slightly arching habit.
Non-toxic, these ferns are a good choice for households with pets, and will not pose a risk to our canine or feline friends.
Where to Grow Lemon Button Fern
If you want to grow lemon button fern indoors, the first thing to think about is the growing conditions that this plant will require.
Light Requirements
One important thing to think about is light. These ferns need a bright position but one with indirect or filtered light rather than in harsh, direct sun which may scorch the foliage.
In their native range, these ferns are sub-canopy plants so indoors, you should aim to mimic the indirect light conditions that they experience in such a location in their natural habitat.
But as long as you do not place them in too bright and sunny a spot, these ferns can be quite tolerant of a range of light conditions.
Temperature & Humidity Requirements
The regular temperature range found inside most homes will provide a hospitable environment for lemon button ferns. However, it is important to remember that like many other ferns, these ferns require reasonably humid conditions.
Homes can easily be low in humidity in cooler climates through the winter months when centrally heated. So it can be a good idea to place one of these ferns in a more humid room – such as a reasonably bright bathroom or near a kitchen sink, for example.
Soil/ Growing Medium
Lemon button ferns need a moist but free-draining growing medium. Though they like consistent moisture throughout the year, they will not like waterlogging.
Ideally, the growing medium that you choose should be loamy, and acidic. An ericaceous houseplant potting mix will be perfect for growing lemon button ferns in containers indoors.
Planting Lemon Button Fern
When planting lemon button fern, pot up a plant you have purchased into a suitable container. A glazed terracotta pot with good drainage holes at the base is a good choice for these ferns. Choose a pot that is just a little larger than the current root system. Water the fern in well but as always with this fern, make sure that excess water can drain away freely.
Caring for Lemon Button Fern
Once you have potted up your lemon button fern and chosen a suitable location for it within your home, you will discover that it requires very little ongoing care. However, you will of course have to think about a few things to keep your fern happy over time.
Watering
The key thing to remember when watering lemon button ferns is that you should not allow the growing medium to dry out entirely.
How frequently you should water your fern will depend on a range of factors including light levels, temperatures, humidity, age, and size. But as a rough rule, you should expect to water around once a week.
Check the growing medium and water when it feels like it is becoming dry at the top, but before it dries out too excessively. Just make sure that extra water can drain away from the base of the container.
Feeding
Ferns generally are not heavy feeders and this small and slow-growing fern is no exception.
But if the growth seems particularly slow and poor, or plants look to be displaying signs of nutrient deficiency, then you can feed every few months during the growing season with a balanced, organic, liquid plant feed, diluted to around half strength.
Pruning
These ferns grow only very slowly and don’t need much pruning at all. But some fronds will commonly die back in the autumn and winter, as well as occasionally at other times of the year.
These fronds can be cut back and removed to keep things tidy and to provide space for new growth to emerge.
Problems
Lemon button ferns are unfussy plants that are often trouble-free. But like other houseplants, some issues can arise. Most problems are related to issues with environmental conditions or care.
Brown, dried fronds, for example, can indicate that there is a lack of water, or that humidity is too low.
Wilting can be caused by overwatering, or too much sun.
Yellowing leaves often indicate sunburn, overwatering, or waterlogging.
These are a few examples that illustrate some of the most common problems that arise when growing lemon button ferns indoors.
Repotting
A lemon button fern will remain compact and as it grows slowly, will not have to be repotted often. Repotting should only be undertaken when you see roots poking out of the growing medium. The best time to repot a lemon button fern is in the spring.
Choose a new pot only slightly larger (by a couple of inches or so) than the old one. Refill it with a new potting mix as you undertake this job.
When repotting, you might also lift and divide an existing lemon button fern to obtain new plants and expand your houseplant fern collection.
An existing fern can simply be lifted and teased apart and sections with some rhizome and some shoots can be potted up into their own separate containers and grown on.
