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Fertilizing Your Boston Fern: The Trick to Feeding This Finicky Houseplant

Fertilizing Your Boston Fern: The Trick to Feeding This Finicky Houseplant

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Boston ferns are among the most popular houseplants. They’re common sights in both living rooms and office environments.

They aren’t as easy to care for as some houseplants, though. Boston ferns aren’t necessarily too tough for beginners to own, but you do need to do things right to get good results.

If you want the plant to grow well, it’s important to plant it in good soil and to water it properly. It’s also helpful to give the fern fertilizer from time to time, but you must be careful.

Continue reading to learn about what to feed a Boston fern. You’ll have a better experience caring for these ferns when you know how to approach feeding them.

What Is the Best Fertilizer to Use for Boston Ferns?

Since Boston ferns are slow-growing plants, they don’t need a lot of fertilizer. Some types of fertilizer might even be too strong for these plants.

You want to use a type of fertilizer that you can easily dilute to keep things safe. Thus, it’s recommended to stick with water-soluble fertilizer options.

One of the best fertilizer ratios is 20-10-20. Using a fertilizer such as this should allow you to get good results.

You only want to give the Boston fern fertilizer once per month. Also, it should be diluted to half-strength to ensure the safety of the plant.

Using too much fertilizer is very bad for these types of ferns. Often, it’ll cause them to change color and it could even wind up making the plant drop its leaves.

So you need to be careful when using fertilizer. When the plant is in its growing season, it’s fine to fertilize it once per month.

During the autumn and winter months, you won’t need to do this nearly as often. Growth slows down to a crawl during this time of the year.

Most experts say that fertilizing the plant every two or three months during the fall or winter is enough. It’s best to err on the side of caution rather than to fertilize the plant too much and regret it.

Flushing the Soil

It’s a good idea to flush the soil every so often to help the Boston ferns. This is especially true during the winter months.

Salts can build up in the soil when you’re using fertilizer. The presence of too much salt can lead to various issues.

This has been linked to problems with Boston ferns dropping leaves. To avoid such issues, you can flush the soil during the winter using distilled water.

Water the plant with distilled water and it’ll flush out the salts. This helps to keep things safer for the plant and you won’t need to worry as much.

You should consider flushing the soil once per month during the winter months. Some people also choose to do this during the autumn.

Can You Use Epsom Salt on Boston Ferns?

Yes, you can use Epsom salt on Boston ferns, but you might not need to. Typically, indoor Boston ferns aren’t going to need Epsom salt.

It’s more common to use Epsom salt on the soil when caring for outdoor ferns. Regardless, it’s good to know that Epsom salts can indeed be helpful.

People sometimes use Epsom salt on plants that are in need of magnesium. It can be a good source of magnesium and sulfur for these plants.

Your Boston fern may need Epsom salt if it is yellow or if some of the fronds have yellow spots. It’s common for Boston ferns that are in need of magnesium or sulfur to have yellow spots between leaf veins.

So this is a method to help the plant out. You want to be careful when using Epsom salts so that it doesn’t wind up being detrimental, though.

How Much Epsom Salt to Use

Using just enough Epsom salt to get the job done should be your goal. Going overboard or splashing the Epsom salt on the plant can be very bad.

You want to create a mixture that contains the right amount of Epsom salt. Two tablespoons of Epsom salt can be mixed with warm water to make a good mixture that isn’t too potent.

Allow the Epsom salt to dissolve completely and then water the fern. You want to water the fern thoroughly as you would when watering it using normal water.

The water should come out through the drainage holes if you’re doing this on an indoor plant. If you’re using this on an outdoor plant that’s in the ground, you won’t need to worry about that.

Be careful when watering the plant. Splashing the foliage with the water will be bad, and that means that you should carefully water the soil at the base of the plant.

Also, you should know that Epsom salt should never be used during the autumn and winter months. Only use Epsom salt on Boston ferns during the active growth season.

Boston Ferns Just Grow Slowly

Keep in mind that Boston ferns are meant to grow slowly. You can help things along by giving them fertilizer during the spring and summer.

However, these plants aren’t suddenly going to start growing exponentially faster than they would normally. It just helps things along a little bit.

So you must temper your expectations when it comes to what fertilizer can accomplish. It’s well worth using, but it’s important to recognize that Boston ferns don’t grow super fast.

You also need to respect the danger of over-fertilization. Be careful so that your Boston ferns can remain healthy and look nice.

Final Thoughts

Now you know what to feed Boston ferns to get good results. You want to use water-soluble fertilizers that can easily be diluted.

It’s generally wise to use a 20-10-20 fertilizer. You can dilute it to half-strength and give it to the fern once per month during the spring and summer.

You won’t need to fertilize nearly so often in the autumn and winter. It’s fine to fertilize the plant every two or three months during this period.

Epsom salts can help when your plant needs sulfur or magnesium. Just be careful not to use too much and don’t splash the foliage with the Epsom salt water.

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