Western sword fern: Diseases and Remedies (2-minute Read)

NOTE: The terms Western sword fern and Polystichum munitum are identical in this text; in reality, Polystichum munitum is Western sword fern’s biological word.

Ferns add texture, interest and beauty to the garden, with many species also thriving as houseplants. The Western Sword Fern (Polystichum munitum) is one of the most recognized varieties of ferns in the world. This common fern is native to North America and can grow up to 4 feet in length.

It is a low-fuss addition to the landscape that does well under trees and in shade gardens. While western sword ferns are usually grown outdoors, they can be successfully grown indoors in planters and containers.

Why does my Polystichum munitum roots have rot?

Root rot on your Western sword fern (Polystichum munitum) can be fatal if not treated with care. For this reason, we strongly recommend that you follow our guide to keep your plant alive if the symptoms occur: Root soft and blackened.
Western

Why does my Western sword fern have gray mold spots?

A particular fungus known as gray mold spots spreads quickly and frequently damages flowers. This fungus is probably to blame if you see any brown (or gray) spots. If you disregard these warning signs, your plant could die.

Our Solution

When you understand the root of the issue, the solution makes perfect sense. The majority of the time, it is caused by the Polystichum munitum being overwatered. We urge you to cut off the infected roots and leaves, remove the affected sections of the plant, and then repot your plant in a fresh container with sterile potting soil.

Why does my Western sword fern have leaf spots?

Leaf This type of disease is one of the most frustrating for Western sword fern owners, we give you all the leads to spot and save your plants that present symptoms such as leaves that suddenly change color, or wilt/droop.

Why are my Western sword fern leaves turning yellow?

In the world of horticulture, yellowing leaves are undoubtedly the most common problem. The two main causes of this problem are overwatering and a lack of nutrition.

When it’s overwatering, simply reduce your watering frequency, and if you think it’s a nutrient deficiency, here’s how to check it:

Each deficiency produces a different yellowing on the Polystichum munitum in question, here’s how to spot them:

  • Yellow patches between leaf veins on elder leaves are the first sign of magnesium shortage. Veins continue to be green while the leaf’s core turns yellow. The leaf’s edges yellow last.
  • Iron deficiency also shows as yellowing between leaf veins, but it hits young leaves on plant tops and branch tips first.
  • Sulfur deficiency starts with the newest leaves, turning them yellow throughout.
  • Insufficient potassium causes the leaf edges to turn brilliant yellow while the interior of the leaf stays green. Older leaves show the symptoms initially, and the leaf edges quickly darken.
  • A lack of nitrogen is indicated by a widespread yellowing. Older, inner leaves are the first to yellow. As the yellowing progresses, it eventually touches young leaves as well.

Our Solution

You only need to respond to the signs mentioned above. A gardening store expert will be able to provide you advice on how to purchase a specific soil to treat a potassium or nitrogen deficiency. Additionally, you can reduce how often you water your plants.

Is my Western sword fern sunburned?

You can easily tell if your Western sword fern (your Polystichum munitum) has a sunburn. In this case, your plant will change color, starting to turn yellow or white, much like it does on us.

Sunburned

As we saw above, if your Western sword fern receives too much water or not enough light, the leaves may also change color.

To find out if the yellow leaves have been sunburned, look at the part of the bottom that is tinted closer to the base. The yellow leaf is probably burnt and not something else if this portion stays greener.

Why are my Western sword fern leaves turning brown?

A plant’s browning leaves are typically a symptom that it has been sunburned and has been exposed to excessive amounts of direct sunlight. Don’t worry; your plant probably won’t perish as a result, but its growth will be negatively impacted.

Should I leave my Polystichum munitum in direct sunlight?

No! Don’t leave your Polystichum munitum (or Western sword fern) in the sun if it displays the symptoms mentioned above; that’s why it’s in such a bad situation.

Our Solution

As explained in the paragraph above, the solution is simple, just place your Western sword fern in a place where the light does not reach it directly, in this way and with a correct watering, your plant should resume its life rather quickly.

Why are my Polystichum munitum leaves drooping or wilting ?

In most cases, this happens when your Polystichum munitum lacks water. This is especially the case for large plants, naturally they need more water than others.

Drooping

You may quickly determine if your Polystichum munitum plant needs water by under-weighing its pot; if it seems light, the soil and roots are probably fairly dry and require water.

Our Solution

If the soil in your plant’s pot is completely dry, you will need to start by moistening it so that the roots will also benefit from the water. A common mistake is to drown the Western sword fern right after a dry period thinking that it needs a lot of water.

This is the case, but giving too much water at once is the best way to finish it off, you should actually water the soil normally, resuming a quiet watering rhythm.

Caring Tips for Polystichum munitum

Water Occasionally

Water is necessary for your plant to live, but timing and amount of watering must be balanced. Overwatering could have disastrous effects on your own name, as we already mentioned.

You can tell if your plant needs water by touching the soil; if it still feels damp, it’s usually preferable to wait a few more days.

Always keep temperatures stable

It is also a good idea to keep your Polystichum munitum at a stable temperature (especially if it is kept indoors!). At GreenShack, we generally recommend staying in the 65 and 85 degrees F range. Of course, do not place your Polystichum munitum near a source of hot (or cold) air such as A/C units, radiators or the like.

Keep your Western sword fern Dust-Free

This one concerns indoor plants, just like on your furniture, dust is also deposited on the leaves of your indoor plants, the problem is that it can prevent them from receiving the necessary light, this would slow down (or even stop) the photosynthesis process, and eventually, they would lose their colors.

For your Western sword fern, this would be a true descent into hell, and it would also appease the pests.

To remove the dust, gently rub the plant’s leaves with a microfiber cloth. Dust can be removed more easily with a damp cloth, but stay away from corrosive substances like rubbing alcohol!

Keep drainage in mind

If you have a tendency to overwater, you should be mindful of your drainage, and if they don’t already have them, we suggest selecting a saucer and a pot with drainage holes.

If your pots don’t already have holes in them, you can add volcanic rocks (or any other pebbles with holes) to the bottom of your pot in the meantime. This will assist in creating a channel and keep the water from pooling there for an extended period of time, protecting the roots from decay.