Having a sufficient amount of bedding for your worms to live in is very important, especially during periods of very high or very low temperatures. Worms will retreat to these bedding areas which are more commonly castings and partially eaten food from previous feedings.
Bedding is different from feed; bedding is more of a safe space for worms to retreat to whereas the feed is applied to the top of the farm for worms to come up and work in then retreat back to the bedding layer. Depending on the design of your worm farm this will affect how much bedding will be available, cold areas will benefit from having a thicker bedding layer as the bedding will hold the warmth and give shelter for your worms.
If you’re using a “Can’O’Worms” or “Worm Café” then we recommend you always maintain one full castings/bedding layer for your worms to live in.
While most manufactures recommend the use of a worm blanket or cover, we do advise you use caution and take your location and the temperatures of your area into consideration. Cooler climates will benefit from the extra layer of insulation, while northern regions are best to avoid the use of a cover as this can trap in excess heat produced by the composting process and by the worms activity and cause the farm to overheat, it is always important to monitor your farm and if you believe a blanket is required then just keep an eye on how your farm is behaving, if it starts to feel warm or the worms are looking unsettled then remove it.
Now this is why you would have set up a worm farm to begin with, worms are constant eaters, they are always hungry and on the search for food. The general rule for feeding your worms is to only feed them at the rate they are eating, by only applying more food to the worms once the majority of the previous feed has been consumed then you will maintain a healthy farm and a healthy farm is a productive one. A good method to help prevent over feeding is to apply the food to half the worm farm at a time, once the food is mostly consumed then apply the next feed to the other half of the farm. The worms will happily move side to side as the food is added.
If worms are over feed then you risk the farm turning anerobic and the worms will die off due to the lack of oxygen, if you believe this might be starting to happen then remove any excess food and turn the top layer over with your hands or a fork, this will help reintroduce oxygen and release the buildup of carbon dioxide. It may take a while for the worms to return to the feeding layer so be patient and only add a small amount of food to one side of the farm and monitor the worms activity, you may find they have gone down into the bedding layer for safety.
As for what you can feed your worms, well the general rule there is that a worm will eat anything that was once living but no longer alive. Worms do not have teeth so the size of the food and the consistency when you add to the farm is a big determining factor on how fast the food is eaten by the worms.
The finer the particle size the easier it is for the worms to ingest and the faster they will consume the food. People have had great success in mashing or Blending up scraps before adding for the farm in a slurry form, another way is to freeze the food then add to the farm. The freezing process causes the foods cells to rupture then when it thaws out it will be mushy and easy for the worms to eat, this is a good tactic to use in summer when temperatures rise and your farm may benefit from the frozen treats.
We advise against adding meat, dairy, citrus, chilies and other spices to your farms, while worms are omnivores, they will require other organisms to partially break down these products before the worm can get involved. These products are best to be added to a compost pile rather than your worm farm.
If in doubt, leave it out. It is always better to be on the safe side. Once your confident with your worms you can always experiment with different foods to find what works best and how your worms react.
The moisture content of your worm farm is very important. As mentioned above, Worms require their skin to be moist for them to breath. The ideal moisture level for a worm farm is 40%, this is the equivalent to a few drops of water when a handful of bedding is squeezed. A farm that is too dry will deter the worms from the feeding layer as they dive to the bedding layer where the moisture will remain for longer and a farm that is too wet will drive the worms to the surface as the oxygen in the farm is driven out by the water and so too are the worms.
Another important aspect of the farm is to ensure it is free draining, you want to avoid any water building up as it can go anerobic in the bottom of the farm, while a free draining farm will require more often watering it will ensure a fresh supply is always available to the worms. By adding 1-2 litres of water through your farm per week this will ensure your worms always have access to fresh water, be sure to collect the water as it comes out of your farm and put on your garden. As the water passes through the farm it will collect some of the nutrients from the castings which makes for a fantastic natural liquid fertilizer.
The frequency and volume of water will greatly depend on the food being fed each week. Most kitchen scraps contain a high level of moisture which will leech into the farm requiring less water to be added while more carbon rich feed (paper, cardboard, dry leaves etc) will often be dry and require soaking before being added. The time of year and your location in Australia will also have a diverse effect on watering of your farm. Dryer areas will require more frequent watering whereas cooler climates will require less water to be added.
A general guide is to give your farm a light mist 2-3 times per week. Should your farm become too wet, add dry shredded paper, cardboard or pine shavings to absorb the excess moisture and give the farm time to drain/evaporate before adding more food or water.
Worms are hardy creatures and can tolerate a variety of temperatures, the ideal temperature for your farm is between 18 and 25 degrees C, now this is bedding temperature, not air temperature. It is always handy to have a probe thermometer on hand to check your farms temperature. If you don’t have one available then a general rule is to place your hand on top or to dig the surface back and if the bedding/feed feel warm then it will be too warm for the worms.
While worms can survive well into the single digits, however hot weather can be very harmful to your farm, a temperature of over 30 degrees C is considered to be at a dangerous level, if you find all the worms are on the surface or trying to escape then your farm may be showing signs of heat stress, giving the worms a spray with cool water will help, leaving the lid off the farm and allowing the breeze to blow over the top will cause an evaporative effect and draw some of the heat out (but be cautions as Australia’s native birds are very opportunistic and will help themselves to a feed if unattended, a piece of light shade cloth or fly screen laid over the farm will prevent the theft). During times of extreme heat, people have had success with spreading some ice cubes or frozen vegetables (as mentioned above) over the top of your farm to cool the feed down. It is good practice to minimize the amount and frequency of feeding during these times of high heat, by keeping any eye on your farm you will be able to see what your worms need.
You need to take temperature into consideration when you are deciding the location of your farm. Store brought farms like the “Worm Café” and the “Can-O-Worms” will work best by being in complete shade all day, due to their black plastic construction even a small amount of direct sun can cause them to heat up very quickly. Cooler climates can benefit from some filtered sunlight but direct sun is still not advised.
Your worms are not alone
As your farm becomes more established you will start to see more and more insects and organisms scuttering around the feed when you open the lid. “What are all these other organisms crawling around my farm and are they harmful?” This is probably one of the most common questions we get about worm farms, and sometimes complaints.
Your worm farm is a complex ecosystem. Whilst worms are key to this ecosystem, they are only one part of the natural cycle and they are actually towards the end. All these other insects that are scurrying around in the dark are all workers too, they are doing their part to break down the organic matter you have placed in the farm. Organisms like Spring tales are working to control the fungi populations, Soldier fly larvae are also working to break down the food, various species of mites are chomping away at the larger and more dense pieces of food and while they may seem like a pest, they are very important. Worms don’t have teeth therefore they cannot bite into larger food and have to wait for it to decompose to a soft state before they can work on it, this is where the other organisms come into play, they start working on the food and the worms come up behind not only feeding on the decayed food but also the manures left buy the other insects etc.
The importance is a balance in your farm, if one species starts to overpopulate then you may start to have an issue (Excluding worms of course). By blending or mashing the food you will enable the worms to work on it a lot sooner reducing the available food for the other organisms, if mites or Spring Tales start to become numerous then place a piece of watermelon or rock melon rind or similar and leave for about 24 hours, after which you can remove the now covered rind and dunk in a bucket of water to remove the insects, then place back in the farm and repeat till the population is reduced. Soldier fly larvae are best removed by hand, don’t worry they won’t bite and if you have chickens they will love the treat. Ants are another common visitor to a worm farm, while they too play their part, they are opportunistic and will attack any worms they can get. The best practice is to stand the legs of your worm farm in margarine containers of water, this will prevent them from gaining access to your farm.
It is best to avoid meat products, while the worms will eventually process the meat it will take some time and can attract unwanted pests, if you do put any meat in then be sure to dig a hole and burry it so that it won’t smell and attract those unwanted pests.
Reaping your rewards
As worms consume the food they leave behind castings or worm poo. For the gardener this is black gold. The worms cast is extremely rich in plant available nutrients and active soil bacteria and microbes. As your worm farm fills with castings and the layers have been added to keep the worms moving up with the food then it may be time to remove the lowest layer for castings harvest, remember to make sure you leave one full layer for the worms to retreat to in case of temperature extremes or if a problem develops in the feeding layer.
These full layers can be quite heavy so you may need the help of a friend to separate them from the main farm. Once removed you can empty the contents straight into your garden you onto a tarp etc for you to store and use as required.
The worm castings can be added to your garden then with the use of a fork turned into the existing soil, be sure to add a thick layer of mulch, this will protect those microbes and bacteria and allow them to continue working, another use is to add a handful to the hole when planting new plants, by putting the casting near the roots, the plant can absorb those nutrients and give it a strong start. A popular use for castings is in worm tea, this involves soaking the castings in a bucket of water at a ratio of 1 part castings to 5 parts water where the nutrients leech into the water to be fed to the plants in a liquid form, there are various methods from plain soaking in a bucket to more complicated bubbling methods with the use of air pumps to multiply the microorganisms. There is lots of information and instructions found online. Be sure to use the tea straight away, due to the live bacteria in the water the tea can turn anaerobic very quickly if stored.
Worms are very resilient creatures and will handle a lot of abuse so while you are learning about your farm don’t be concerned if you make a mistake, the worms will forgive you.
Written by Rohan Watson of Rural Earthworms
Queensland distributor for Worm Affair.
Murphy D. (1993) Earthworms in Australia, Hyland House Publishing Pty Ltd.
Hyland House, 387-389 Clarendon Street, South Melbourne, Victoria 3205
Windust A. (1997) Worm Farming Made Simple, Published by Allscape
Mandurang, Victoria 3551, Australia