Red Wigglers (Eisenia fetida) are composting worms, and we are going to use them to simplify feeding our plants without having to buy a lot of supplements. They’re obviously reddish and they flail around blindly when disturbed.

These little guys have been deliberately used in composting for centuries, and unintentionally, in Europe where they are native, probably for as long as they have been composting.

While it is likely that your potting soil is fertilized, these nutrients will only last so long without being renewed. One of the most traditional approaches to renewing soil is composting, but in this work, I am not assuming you have any outdoor space available to you for that purpose.
If you have community composting or access to compost, this is much easier than working with worms. You would simply re-enrich your soil in your containers with their compost, and contribute your wastage to their compost pile. In many areas these days, you can avoid this work altogether. You may or may not want to do that if you have such a resource available to you.

Some people just enjoy raising worms. By the time you have reached the portion of this book that is about creating the garden room, I hope that I have given you a good understanding of what is involved.
 
I do not have outdoor space to work with at this time. I may manage to work that out with some of my neighbors. I have in the past, and if I did now I would keep an outdoor composting pile. If you happen to have outdoor space, I would like to refer you to Compost City, by Rebecca Louie, who covers a wide variety of composting, both indoors and outdoors. Hers was not the only composting book I have read, but it was probably the best. She really packs a lot of information into a pleasant and easy reading experience. I finished it in just a few sittings.
 
Worm food is described in the same terms as the basic ingredients of a compost pile. The keywords are ‘greens’ and ‘browns’. Greens are fresh plant material, and cut fine, while browns are dried plant material that you don’t have to bother cutting. The worms like to occupy the browns as habitat while feeding on both the greens and the browns. Really they are feeding on the things growing on the greens and the browns, but you do not have to concern yourself with that.
 
Most people mix the browns with shredded brown paper. If you were to only add dried leaves as browns, they can tend to stick together when wet. When this happens lactic acid bacteria tend to thrive, creating an acidic environment that is unhealthy for your worms. They will avoid it if they can, but they will die if they cannot.
 
I cover two sorts of worm containment. The standard worm bin and the Garden Tower Project 2 salad tower. In the standard worm bin, brown paper is essential to avoid the lactic acid problem. In the salad tower, I have found that if I don’t wet the leaves first and do not crush them they tend to absorb moisture from their surroundings because it is very damp within the tower. However, I have gone back to mixing leaves with brown paper after that experiment just to avoid the concern.
 
You will read, in books about vermicomposting with worms, that they can digest coffee grounds. This is true, but you do not want to only feed your worms coffee grounds. I point this out because, for those of us who make pour-overs in paper filters, it is very easy to just put the cooled grounds and filter into the worm bin and be done with it. I don’t have hard data on this, though I would like to see some. I can’t tell you exactly how often you should give them the coffee grounds, but about once a month has worked for me.
 
There are many sorts of worm-based composters these days. The basic concepts are so simple, that it lends itselve to multiple solutions. Please don’t think that because I only cover these two, they are the only approaches to worm containment. They are not. However they are the two that I have extensive experience with, and so I have restricted myself to those so that I can provide you with very good information on those two solutions.

Worm Bins

While, as I just said, there is a large variety of these, one is by far the most common. These have been commercially available for quite a long time now. Many gardeners have been using these for decades. You can also make your own worm bins, and save a little money. If you search the internet for worm bins you will find a number of sets of instructions for their construction.
 
The prices on these have gone up. I checked again while writing this section, and must admit I was rather surprised what they get they manage to get for them these days. The one I used for many years was a Worm Factory brand composter, with three trays.

These, and many others, are basically a plastic box on legs with a spigot and a lid. It also has three additional layers of trays, effectively increasing its height and capacity. The bottom of each tray is a screen that allows the worms to pass between them while retaining the other contents, which be their food, bedding, or waste. The spigot is used to extract a substance called leachate, which you feed to your plants, after very heavily diluting it with water.

While I have read some suggesting foliar spraying of leachate, I have never found this to be a good idea. Rather I base water, that is beneath the leaves, using a weak solution that is 20 parts water to 1 part leachate. It’s easy to give your plants too much, or especially to burn the foliage. Worm leachate is pretty concentrated stuff when you get it from this sort of worm bin.

Red Wigglers arrive with pests

Imagine filling your nice integrated planter and bin with new sterile soil, going to add your worms and seeing aphids and earwigs crawling out of the material they were shipped in. I’ve had that feeling, and it’s painful. I later learned that sometimes those insects were harmless soil mites and only looked like aphids. Still, you don’t need them.

Before you rush out and buy some red wigglers, be aware that they almost always arrive with pests that you do not want in your indoor garden. Many of these are more of a problem in the salad tower than they are in a regular worm bin where they are less likely to survive.

Other creatures are almost certainly there in your worms, even if you bought them semi-dried and they were shipped to you. If they arrived that way, you will be instructed to mist them with water to reconstitute them. Do this away from your bin or tower and rinse the worms, place them in another container and then take them to their new home.

Initial Setup

When you purchase this sort of bin and have secured some worms, you need to prepare the bin. Most of the commercially available bins of this type these days come with multiple layers of trays. These trays stack on top of the base component that has the spigot. The unit will also come with a lid that is meant to keep the light out.
Before adding worms to the unit, you should add the bedding. This should be a combination of shredded brown paper and tree leaves. As I mentioned before you need the paper so that the leaves will not stick together too much and cause the environment to become acidic.

Some people do not restrict themselves to brown paper or paperboard tubes and instead will use bleached paper, that they perhaps received as junk mail. This does, according to the reports I have heard, work. That is the worms survive this and continue to thrive. I don’t do this because we will be eating the ultimate results of all this. It is possible that I am overly cautious.

Trees have deep root systems and complex relationships with soil fungi that enable them to take up nutrients. While the plant pulls most of these nutrients from the leaves when they are drying, some remain for your plants after composting.

If you are drying your vegetable trimmings first and adding them to the worm bin as browns, you can add as many as you can get in there within reason. These will have more nutrients in them because they were cut green as opposed to the plant dropping them.

For the same reason, if you happen to come across a branch that has been trimmed or a fallen tree whose leaves have dried, these leaves are better than those which the plant dropped in the fall or from heat stress because they retain more nutrients. In my experience, these are not hard to find. People are not usually very attached to the leaves in their yard waste.

You should fill the entire lower tray with the damp leaf and paper combination. They should not be dripping wet. If they are, let them dry a bit first. It’s easy to get the amount of moisture right using a misting spray bottle. The paper and leaves should feel, as Rebecca Louie says, like a wrung-out sponge. Just damp. Once that is done you should add your worms, being sure that you have read the section Red Wigglers Arrive With Pests.

Over the worms and the bedding, you should place a damp, not dripping, brown paper bag or two, as needed to cover the surface of the bin. The lid for the worm bin goes directly on top of this layer of paper. You will need to replace these occasionally as they rot.

That paper bag layer is your moisture monitor. It will slowly dry out and you will want to mist it again in order to keep it slightly damp.

Feeding your worms in the worm bin is a simple matter of occasionally adding misted dry leaves to the bin as needed, and a tablespoon or two of finely chopped fresh greens about once a week. They are very fond of any avocado that might have gone bad on you, and also mango peels, but they are not really very picky. They do not like aliums that is the family of plants that contains onions and garlic. They should also never be fed concentrated foods like rice, beans, or peas. These will simply rot in the bin. Any green food you give them should be chopped fine unless it is very soft like the spoiled avocado which the worms can go right through. You want to scatter a tablespoon or two of these greens out beneath the paper bag covering and on the leaf and paper bedding, leaving no concentrated pockets. You should not feed the worms again until the previous food is basically gone. Concentrated pockets will produce hot compost which is not what you want in your worm bin. Instead, you want to encourage the growth of other organisms on the browns and greens, because these are what the worms actually consume.

You do not have to worry about too many browns, and I have gone for long periods adding dried garden waste and nothing else. The growth that the worms eat will grow on them just fine. I do not chop it fine when it is leaves because I do not want them to stick to each other too much when wet, and their natural shape helps to avoid that.

Harvesting Leachate

Worm bins of this sort produce two gardening products, leachate, which is the liquid product, and castings which are the solid product. Worm bin leachate is a very concentrated fertilizer and it must be used with care to avoid burning your plants. One of the advantages of using the salad tower is that this comes through already diluted.

While I have read some advising using diluted worm leachate as a foliar spray, I have never found this to be a good idea. Rather the leachate drained from the tap of a regular worm bin should be used very diluted with water at a 20:1 ratio and this should be used to base water your plants. The gardening expression ‘base water’ means to water beneath the leaves without getting them wet. Some plants are very sensitive to the leachate, while others hardly mind at all. They all are fine with base watering in my experience.

Base watering, as a rule, is much less problematic in general than getting the plant wet, and I am recommended that those of you new to gardening, who may not know the result of the foliage being frequently wet, stick to base watering.

You should keep up with draining off the leachate and not allow it to accumulate. Some people leave the spigot open and a larger jar beneath it to catch all the leachate that is released. If you are unable to drain it daily, then this is probably a wise choice. The leachate does not keep and will change across time, possibly becoming more acidic. Also, there is a critical substance named urea that provides usable nitrogen to your plants that degrades in a few days. Your worms, the fish in aquaponics and you for that matter, humans, produce this stuff as do the other animals. I’m trying to avoid unnecessary complexity, so I am not going to describe the chemical processes involved, because all you really need to know is that it goes bad across time and should be used fresh.

I have seen people say that they can keep it for as long as a month, though I have never done that. I used mine within days. As with the leaves, the biggest risk is that anaerobic fermentation begins and that the liquid will become too acidic. If for some reason you want to store the leachate longer, you could bubble some air through it so that there is too much oxygen suspended in the water for anaerobic (this means they can live without oxygen) bacteria to develop.

Another option is freezing it. I actually freeze most of the water I use for slow release and pest control. I discuss that more in a later section.

Adding Additional Trays

After a month or so that first tray should be partly filled with the shiny black worm castings. It is time to add the next layer to the worm bin. Simply remove the lid, remove the paper bags from the surface of the lower layer, place the new layer on the old layer, fill it with damp paper and leaves as before, cover these with the bags, and then place the lid on it. Continue feeding as normal, now under the bag in the new top layer.

The worms will migrate upwards through the material on their own. Most of these units ship with two or more trays for the worms. About a month after the addition of the last tray it will be time to do your first harvesting of worm castings.

Harvesting Castings

Things are about to get messy. Before you get started, you should pick an area that is easily cleaned to do this. Outdoors is good or a large sink. You will also need to briefly set down the tray being emptied and a stack of trays unless you have assistance. This step is much easier for two people.

You will leave the castings that are in the bottom section with the spigot alone. These will slowly decompose into your leachate and more will be pushed down from above. These castings sit in the potent leachate much of the time and are a little hazardous for use for that reason.

If you have two people, one should lift all but the lowest tray from the stack, the second person should lift the lowest tray, and place it on a flat rimmed sheet pan to catch any drips, while the first person returns the other trays to the base. This is the only step you want two people for. If there is only one, you will need to set down those upper bins on something briefly, like another tray, so be prepared.

At this point, we have a tray full of worm castings, worms, and possibly some undecomposed material. You want to get most of the remaining worms from the worm castings. Most will have already migrated upwards, but there will be stragglers.

You will want three buckets for sorting. One will hold the unsorted material, one will hold the worms you pick out and another will hold the mostly worm-free castings. You simply dump the contents of the tray into the first bucket. You then fill that tray as before with the shredded paper and leaf combination that you are using for bedding. More the paper bags from the former top tray as before, and onto the top of the just refilled tray and use it as the top tray. Red Wigglers don’t mind being crowded together and I never had problems with them trying to crawl off during this portion of the process. However, I also did not dawdle while doing it.

The worms that you sorted can simply be dumped under the damp paper bags on top. They’ll sort out what they are doing and find the food. I use a fancier bin now and the process is different, so I was unable to measure how long this process takes, and I can’t remember ever actually timing it, but it’s not a very difficult task, once you are used to it. Maybe ten or fifteen minutes, depending on how picky you are about getting all the worms out. You will not get them all, there will be tiny ones that you will almost certainly miss. These will end up in your potted plants. They aren’t a problem there.

Use the worm castings can be used to top-dress your potted plants. ‘Top dress’ is a gardening term that means to apply some soil amendment to the surface of the soil, as opposed to mixing in into the soil. I usually keep them back away from the stem of the plant by about an inch. I am probably a bit overcautious from having previously accidentally burned plants with leachate.

When you base water the plants, the nutrients from the worm castings will wash into your soil, feeding your plants. I usually top dress with about a half-inch of castings, though I have read others who use a whole inch. For those that choose not to go through with the whole worm thing, you can buy the castings at most stores that sell gardening supplies. These have usually been dried. Follow the instructions on the package.I currently prefer the Garden Tower Project 2 Salad Tower, which is both a worm bin and a planter. I have documented this in a separate article.

What if I don’t want to deal with worms?

That’s okay. You can buy fully composted compost in bags. One of the nice things about using compost as opposed to more concentrated chemical fertilizers is that it is harder to burn your plants and really easier for beginners. Without getting into the complexities of plant nutrition, the nutrients in compost are in a form that enables to plant to regulate its update. To put it another way, you are not likely to damage your plants with over-fertilization using compost. You can safely mix in a handful or two of fully composted compost, into the soil from a pot, depending on size, before you reuse it for your vegetables. I should probably remind you here that this book is about growing vegetables.

You would not want to add compost to a pot you were planting a cactus or another succulent in, for example. It would cause your soil to retain more moisture than the succulent wants. In the case of some other slow-growing house plant, think tablespoons instead of handfuls. You should be aware that you likely will have to water less. Vegetables have been bred to grow rapidly and will feed more heavily than your ordinary houseplants.

If you decide to use concentrated chemical fertilizers, please follow their specific instructions. I’m deliberately avoiding getting too much into that because I don’t know where to stop if I start. I use Hydroponic Food Production by Howard Resh for that sort of information. It’s a very large topic, full of long organic compound names.

In the future, I plan to include some kit-level aquaponics. At the same time, I will be doing some articles at NeoPeasant regarding identifying nutritional deficiencies in plants. These will probably all be driven by experiences in my own garden room. This will enable me to photograph and accurately document the issues.