Emerald green arborvitae: Diseases and Remedies (3-minute Read)

NOTE: In this article, Emerald green arborvitae and Thuja occidentalis may be used interchangeably; in fact, Thuja occidentalis is the botanical name for Emerald green arborvitae.

The popularity of evergreens is due to their easy-to-care-for nature and the year-round visual interest they can bring to a landscape. One of the more popular arborvitae species is known as ‘Emerald Green’, which is highly prized as a hedge or screen plant, especially in colder climates.

WARNING: Keep in mind that Thuja occidentalis (also Emerald green arborvitae) is toxic to Humans, Cats and Dogs.

Why does my Thuja occidentalis roots have rot?

Root rot on your Emerald green arborvitae (Thuja occidentalis) can be dangerous if left untreated. In order to keep your plant alive, we strongly suggest that you follow our advice if the signs start to show: blackened and mushy roots.
Emerald

Why does my Emerald green arborvitae 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

The answer is obvious once you recognize the cause of the problem. Most frequently, it results from the Thuja occidentalis being overwatered. We strongly advise you to remove the damaged plant parts, cut off the diseased roots and leaves, and then repot your plant in a new container with sterile potting soil.

Why does my Emerald green arborvitae have leaf spots?

Leaf If your plants exhibit symptoms like rapid color changes in the leaves or leaves that wilt or droop, we give you all the information you need to recognize them and rescue your plants. For owners of Emerald green arborvitae, this kind of illness is among the most distressing.

Why are my Emerald green arborvitae leaves turning yellow?

Yellowing leaves are arguably the most prevalent issue in the gardening world. Overwatering or a lack of nutrients are the 2 main causes of this issue.

Reduce your watering frequency when you fear your plants are being overwatered, and follow these steps to determine whether they may be lacking in nutrients:

Here are some signs of yellowing caused by the many deficiencies on the Thuja occidentalis in question:

  • 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.
  • Another indicator of iron deficiency is yellowing between leaf veins, but young leaves on plant tops and branch tips are first affected.
  • Sulfur deficiency starts with the newest leaves, turning them yellow throughout.
  • Leaf edges turning bright yellow but inside leaf remaining green are signs of potassium insufficiency. The symptoms first appear on older leaves, and the leaf edges quickly become dark.
  • Nitrogen deficiency shows up as a general yellowing. Older, inner leaves turn yellow first. As it progresses, yellowing moves outward, eventually reaching young leaves, too.

Our Solution

You only need to act in accordance with the symptoms listed above. You can address a potassium or nitrogen deficiency by buying a particular soil, and a gardening store consultant will be able to advise you on how to do that. Furthermore, you can also limit how frequently you water your plants.

Is my Emerald green arborvitae sunburned?

It is simple to determine whether your Emerald green arborvitae (your Thuja occidentalis) has sunburn. Your plant will change color in this instance, beginning to turn yellow or white, much like it does on us.

Sunburned

As we saw above, the leaves of your Emerald green arborvitae can also change color if it receives too much water or insufficient light.

However, there is a way to tell if it is sunburn; look at the bottom of the yellow leaves, the ones that have a shaded area closer to the root, if this area stays greener, it is probably sunburned, not something else.

Why are my Emerald green arborvitae 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 Thuja occidentalis in direct sunlight?

No! If your Thuja occidentalis (or Emerald green arborvitae) has the symptoms described above, don’t leave it in direct sunlight, that’s the reason why your Emerald green arborvitae is in such a state!

Our Solution

As stated in the paragraph above, the cure is straightforward: simply position your plant’s Emerald green arborvitae so that it is out of direct sunlight. With proper watering and this method, your plant should quickly come back to life.

Why are my Thuja occidentalis leaves drooping or wilting ?

When you become dehydrated, this usually happens. Large plants are more vulnerable since they need more water on a regular basis than smaller plants.

Drooping

An easy way to know if your Thuja occidentalis is lacking water is to under-weigh its pot, if it looks light, it means that the soil and the roots are probably quite dry, and therefore need 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 Emerald green arborvitae right after a dry period thinking that it needs a lot of water.

This is true, but the easiest way to end it is to give too much water at once. Instead, you should water the soil properly, returning to a peaceful watering rhythm.

Caring Tips for Thuja occidentalis

Water Occasionally

Your plant needs water to survive, but it’s crucial to balance the amount and timing of watering. As we previously mentioned, overwatering could be catastrophic for your Thuja occidentalis.

The best way to know if your plant needs water or not is to touch the soil, if you feel it is still wet, it is probably a good idea to wait a few more days.

Always keep temperatures stable

It is also a good idea to keep your Thuja occidentalis 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 Thuja occidentalis near a source of hot (or cold) air such as A/C units, radiators or the like.

Keep your Emerald green arborvitae Dust-Free

This one is about houseplants. Your indoor plants’ leaves get dusty just like your furniture does. The problem is that this might prevent photosynthesis from beginning, which would result in the plants gradually losing their color.

For your Emerald green arborvitae, 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 tend to overwater, you need to pay attention to your drainage, and we advise choosing a saucer and a pot with drainage holes if they are not already there.

You can add volcanic rocks (or any other pebbles with holes) to the bottom of your pot in the interim if your pots don’t already have holes in them. This will help to form a channel so that the water doesn’t pool there for too long (preventing the rot of the roots!).