woman adding worm castings to succulent pot

Worm Castings for Succulents: A Complete Guide

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I studied the business of worm farming long before I knew they were beneficial for succulents. I didn’t think these desert-native plants would need something like worm castings to keep them healthy.

But when you take a plant out of its natural habitat, you’re going to need to give it something special to help it thrive. In this case, you can definitely fertilize your succulents with worm castings and they’ll be all the healthier for it.

If you’ve been thinking about using worm castings to fertilize your succulents, you’ll want to read this first. I’m sharing everything you need to know about worm castings, including what they are, how to use them, and their benefits and drawbacks.

What Are Worm Castings?

Worm castings are a type of fertilizer made from the feces of earthworms. They are an effective way to add nutrients and improve drainage in potted plants. Worm castings are also known to increase microbial activity in the soil, which can improve plant growth.

Benefits of Using Worm Castings on Succulents

Worm castings are an excellent source of nutrients for succulents. They are high in nitrogen, potassium, and phosphorus, which are all essential for healthy plant growth. Worm castings also improve drainage and aeration in the soil, which is important for succulents since they are prone to root rot.

In addition, worm castings help to increase microbial activity in the soil. This is beneficial for succulents because it helps them to better absorb nutrients from the soil.

Worm castings can also repel pests like mealybugs and aphids and improve the overall health of your plants. They have been shown to reduce the incidence of root rot, powdery mildew, and other plant diseases.

Disadvantages of Using Worm Castings

There are a few potential drawbacks to using worm castings on succulents. First, worm castings can have a very earthy smell when they first decompose. This smell will dissipate over time, but it can be off-putting to those who are sensitive to different smells.

Another downside is that worm castings can be expensive if you have a lot of plants to fertilize. If you have the desire to save compost, you can easily grow your own worm farm and have an endless supply of worm castings for your plants.

It’s important to understand that if used improperly, worm castings can “burn” plants, causing foliage to turn yellow or brown. To avoid this, make sure you only use a thin layer of worm castings on the surface of the potting mix, and do not overwater your succulents.

How to Use Worm Castings in Potted Succulents

To use worm castings in potted plants, simply add a thin layer of worm castings to the surface of the potting mix. Water the succulent as usual and allow the worm castings to work their magic!

You can also add worm castings to your succulents’ soil when you’re repotting them. Simply mix a small amount of worm castings into the new potting mix before adding your succulent.

There is no need to overdo it when using worm castings. A little goes a long way. Just add a layer (about 1/4 to 1/2 inch thick) of worm castings to the top of your succulents’ soil up to four times a year.

A good time to work worm castings into the soil is while repotting them. That way you don’t have to worry about disturbing the roots of your plants.

Related: Best Planters for Succulents

The Best Worm Casting Fertilizers

Not all worm casting fertilizers are created equal. When looking for a good worm casting fertilizer for your succulents, look for one that is organic and contains no synthetic chemicals.

Legitimate brands are non-toxic and safe to use around pets and children, but always make sure to monitor any potential allergic reactions.

Espoma Organic Worm Casting Fertilizer

This organic fertilizer is made from 100% pure earthworm castings. It is approved for use in organic gardening. Espoma offers the best price on smaller quantities (3 lbs bag) of worm castings.

Unco Industries Wiggle Worm Soil Builder

Also made from 100% earthworm castings, this brand is OMRI-listed for use in organic gardening. It is ideal for use on all types of plants, including succulents. Unco Industries offers the best price on medium quantities (15 lbs bag) of worm castings.

BRUT WORM FARMS Worm Castings Soil Builder

This organic fertilizer is made from 100% pure earthworm castings. It is an excellent source of nutrients for succulents and other houseplants. BRUT WORM FARMS offers the best price on larger quantities (30 lbs bag) of worm castings.

Worm Casting Questions New Succulent Owners are Asking

If you’re still not sure if buying worm castings is right for you, here are a few more answers that may help you decide.

Are worm castings good for succulents?

Yes, when used as instructed, worm castings can be very beneficial for succulents. They help improve drainage while adding essential nutrients and increasing microbial activity in the soil.

Can you use worm castings for cacti?

Yes, cacti benefit from many of the same things that common succulents do; therefore, using worm castings as fertilizer can be helpful for cacti as well. Just be sure not to overdo it – too much fertilizer can “burn” cacti just like it can burn other types of plants. A thin layer on the surface of the potting mix should be plenty.

Do succulents need worm castings to survive?

No, succulents do not need worm castings to survive. However, they can be very beneficial for healthy plant growth. If you’re looking for a way to give your succulents a little boost, using worm castings is a great option.

Can I use worm castings on indoor succulents?

Yes, worm castings can be used on indoor succulents. It is non-toxic and there are options approved for organic gardening.

Are worm castings safe for pets and kids?

Yes, worm castings are safe for pets and children. However, as with any new product, it’s always a good idea to monitor any reaction to make sure they don’t have any allergies.

Can I use worm castings instead of fertilizer?

No, you shouldn’t use worm castings instead of fertilizer. Fertilizer is a necessary part of succulent care, and worm castings should be used in addition to fertilizer, not as a replacement.

Do I need to add worm castings every time I repot my succulents?

No, you don’t need to add worm castings every time you repot your succulents. Plan on treating healthy, mature plants once per year, and growing plants up to four times per year. Just mix a small amount into the new potting mix before adding your succulent.

Do worm castings have a shelf life?

Yes, worm castings have a shelf life. They will remain viable for 2-3 years if stored in a cool, dry place.

What is the best way to apply worm castings to my succulents?

The best way to apply worm castings to your succulents is to mix them into the potting mix before repotting. You can also top dress the soil around your plants by sprinkling a thin layer on the surface and watering it in.

Related: How to Care for Succulents Outdoors

Give Your Succulents a Healthy Treat

As you can see, there are many benefits to using worm castings as fertilizer for your succulents (and cacti!). If you’re looking for an organic way to improve drainage and add nutrients to your plants, give worm castings a try. Just be sure not to overdo it – a little goes a long way with these powerful fertilizers.

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