How often to water a worm bin | Summer, Winter + Rainwater Tips

Worms in worm bins need to be kept moist so they can breathe through their skin. Add water to a dry worm farm every second day and cover it with a worm blanket until the bin is moist again. In summer water the worm farm every 2-3 days in Winter flush the worm farm once per week. Add water to the worm farm until you see it flow out of the tap.

This article will explore all you need to know about watering your worm bin including how much, how often and how to adjust for the weather.

Watering a worm bin throughout the year

The amount of water you will need to add to a worm farm will differ depending on the time of year. Over winter, you may only need to give it a light drink once every week just to flush it through. This will also give you some extra worm juice.

In Summer, worm farms need to be checked every day to see if they have dried out on the top levels. I like to add a spray of water to my worm farm every 2-3 days just to keep the worm farm moist.

If you add a lot of moist food like watermelon, tomatoes and fruit you may find that you need to add less water.

How to prepare the water for a worm farm

Many worm farmers will recommend allowing water to sit in a bucket for 24 hours before giving it to the worms. This will allow most of the chlorine to evaporate. This is important for areas with highly chlorinated water as the chlorine can build up in the worm farm.

For me, I never need to do this as our water is not very high in chlorine. Because my worm farm is made from Styrofoam it stays moist for a long time and only needs to be topped up with a small amount of water.

Larger, worm farm towers or bins will need more water as they are less insulated and will lose water faster. They are also larger with a bigger top surface area which gives them more opportunity to lose water.

Worm farm blankets help to keep bins damp

Worm farm blankets are essential to keep the moisture in the worm farm and will minimize the amount of water lost. This will help to reduce the amount of water you need to add to your worm farm.

While you can add a small amount of water to flush the worm farm, as long as the bin is moist, the worms will be happy.

A flush of water can help if your worm farm starts to smell. If you are getting flies, gnats or if you notice ants coming in to your worm farm a flush of water is a great way to help out.

How much water to add to worm bins in Summer

Summer is the most important time to keep an eye on your worm farm and add water to from once per week to every day. In very hot areas, worm farms will dry out quickly even in the shade so spray the top with water gently in the morning before a very hot day.

Keep the tap open at the bottom to let the excess water drip out throughout the day. This worm juice can be diluted and added to your garden. Just add more water so it looks the color of weak tea and put it on established trees, shrubs or in your compost bin.

How much water to add to worm bins in Winter

The amount of water needed for a worm bin in winter will depend on your climate. For areas that get snow, your main aim will be to protect your worm bin with layers of straw and a strong cover. This can be kept covered without adding more water until the weather warms.

For areas with a milder winter like those in tropical or sub-tropical areas you may need to add water once or twice per week. I like to add a small amount of water in the winter as we get minimal rainfall and this will keep the top of the worm farm moist.

If your water is high in chlorine, let it air out for 24 hours before adding. If you have rainwater, this can be added straight away as it will not contain any chemicals.

Why worm farms need water

Composting worms kept in worm farms need moist conditions because they breathe through their skin. Their skin needs to be kept moist so they can absorb the oxygen and life happily in your worm bin.

Worm colonies will thrive in moist and dark conditions and combined with regular food you will have worms breeding quickly and breaking down food scraps.

If worms and their bedding dry out they can die quickly.  Mixing worm bedding materials together like coconut coir, garden soil and straw will feed the worms and help to keep the moisture in.

Placing worm farms in shade will help to prevent them from drying out. Black worm bins in full sun can heat up quickly so place them in full shade to prevent this from happening.

What type of water do you put in a worm bin

Worms are sensitive to chemicals so if your tap water has high amounts of chlorine it can be bad for worms in the long run. Placing the water in bucket and leaving it outside for 24 hours will allow the chlorine to evaporate.

If you have water that is lower in chlorine or rainwater then there is no need for this step. I have always added tap water straight to my worm farm and there haven’t been any issues. If you are worried, just leave the water outside just to be sure before adding it to your bin with a watering can.

How often to water a worm bin | Summary

Worm bins should be watered around once per week in the cooler months and every 2-3 days in the warmer months. Adjust the amount of water depending on the amount of rain you are getting and flush it with water to clear it out and prevent pests.