How to Choose the Correct Garden Water Butt: Water Butt Size Guide

Garden Water Butt

Water is a valuable and limited resource, and it is crucial for the growth of your plants. To save helpful water, you can collect rainwater in a water butt instead of always using tap water for your plants.

There are many different sizes of water butts available. You need to choose the size that will be right for your garden’s needs.

How to chose the correct garden water butt can best be answered by considering your needs for such an object. What material will you want – plastic or metal? The design is essential, and it must have a lid to keep out debris and garden creatures. The water butt size guide will help you select the right size for you. It’s mainly dependent on the size of your garden, the hanging baskets, the size of your lawn, and other watering needs – not to mention the size of your budget.

A water butt is a container of any shape, style, and size you can use to store rainwater. This container collects rainwater to ensure you have a valuable supply of water for your garden.

Water butts are not only valuable for your garden. They can help you save on a lot of things. They can also be beneficial to the growth of your plants. Additionally, they can make your garden more beautiful because they are available in a wide range of styles.

How to Choose the Correct Water Butt

Water butts are available in a wide range of materials, designs, and sizes.

  • Materials

Water butts are commonly made from steel or plastic. Plastic water butts are cheaper. Some plastic water butts are made from recycled plastic, making them eco-friendly. Steel water butts, though, are more durable, heavier, and more expensive.

  • Water Butt Designs

Most water butts can be placed in the corner of the garden. Some of them can be mounted on the external wall of your garden. Steel water butts are designed to stand on the ground.

It is important that you choose a water butt with a lid to keep debris, leaves out of the water. It will also prevent curious animals from getting into the collected rainwater.

Water butts are available in a range of designs. While the barrel type is the most common, you will have a lot of fun choosing from the many decorative designs and colors available.

  • Water Butt Sizes

The smallest water butt size available in the market has a 100-liter water capacity.

Smaller water butts are usually 50 inches high, including the stand and 14 inches wide.

The largest ones are within the range of 1,500 liters, 2,000 liters, and 3,000 liters.

Larger water butts can be as high as 80 inches (200 cm) with a 48-inch (120 cm) base.

The size of your garden will determine the size and water capacity of the water butt you need.

If you have a small garden, choose a water butt size with a capacity of under 200 liters of water. If you have a large garden, you can opt for a water butt with a total of 200 or more liters of water.

Before choosing from a range of water butt sizes, take into consideration these factors:

  • Size of your garden. While the common notion is, the bigger the better, avoid a water butt that is too big for your garden. A water butt too large for your garden may dominate your outdoor space and affect its aesthetics.  
  • How much water you may want or need to store in the butt. An average-sized water tank has a capacity of around 200 liters of water, more than enough to water multiple times an average-sized garden with still some ample amount of rainwater remaining in the tank.

Some large water tanks have a capacity of about 550 liters of water.

You should also think about the various gardening tasks you do and how often you do them. Do you water flowers, hanging baskets, and plants, or do you need to water just your lawn?

It is essential that you have enough water for all these watering tasks. Always remember to overestimate the amount of water you need because storage levels of your water butt can quickly go down.

  • Aesthetics of your garden. Ensure that your water butt does not stick out like a sore thumb in your garden or next to your home. If you have a small property, a large water butt may look bulky and not an ideal match.

Common Water Butt Sizes

  • Most garden supply stores carry water butts in these sizes


  • Small – 50 to 150 liters of water capacity


  • Medium – 160 to 245 liters of water capacity


  • Large – 250 to 550 liters of water capacity


  • Extra Large – 560 liters to as high as 13,000 liters of water capacity.

Most homeowners prefer water butt sizes around the 200 liter-sized mark.  The most commonly purchased water butts are those with 250 liters and 150 liters water capacities.

How to Choose the Right Water Butt Size

In choosing the right water butt size, focus not only on the size of your garden, but on the type of soil you have, too.

Here is a technique you can use to ensure you choose the right size from the many water butt sizes available.

Imagine watering your garden with a watering can. A standard watering can has a capacity of 7 liters of water. The next question is, how many watering cans will you need to sparingly water your plants?

A 120-liter water butt can fill up about 17 watering cans. A 200-liter watering butt can fill up 28 watering cans and a 300-liter butt, 42 watering cans. Here is how long rainwater in your watering butt will last depending on the amount of water you need:


1 watering can 2 watering cans 3 watering cans 4 watering cans
120-liter water butt 17 days 8 days 5 days 4 days
200-liter water butt 28 days 14 days 9 days 7 days
300-liter water butt 42 days 21 days 14 days 10 days

If your garden requires more than 4 watering cans and you only have a small open space, you can have several small butts strategically placed around your property.

If you only have one downpipe in your garden, you can quickly join multiple water butts with a connector kit.

Here are a few estimates on the water requirements of some plants to give you an idea of the water butt sizes you can choose from. These estimates do not take into consideration weather conditions, temperature, and the size of the plants.

These estimates are also based on the assumption that you will be hand-watering your plants during warm, dry weather.

  • A grow bag with one or two tomato plants will need about 2 liters of water per day during warm weather.


  • A 7 feet by 7 feet plant bed with shallow-rooted plants will need about 3 liters of water per day. Its water consumption will also depend on the type of soil, plants, and weather conditions.

The size of the area where rainwater is going to be collected is also a factor to consider when picking the right water butt size.

You will also need to consider the access size to your garden. A large-sized water butt may be too big for your garden gate or front door. If this is the case, you can consider buying multiple smaller water butt sizes.

An average adult can easily lift a 200-liter capacity plastic water butt. Two people may raise up a larger water butt made of steel.

How Does a Water Butt Work?

A water butt works with a simple concept – rainwater is caught in a drainpipe and flows into the water butt. Stored water can then be used to water your garden.

A water butt collects rainwater from the roofs of your home, your garage, or any garden structure that has a gutter and downpipe that goes through the drain at ground level.

It is easy to install a water butt. All houses have a drain pipe. Install a diverter to your drainpipe to allow rainwater to flow from the drainpipe to the water butt.

Water butts come with a tap that can be installed on a predrilled hole. Some water butts arrive with a second tap where you can attach a hose. Special accessories are also available to purify, filter, and keep water collected in your water butt fresh.

You can also install a water butt pump inside the water butt to pump water with force into a hose. This will allow you to water your garden easier and more quickly.

A water butt with a water diverter collects water from the downpipe and lets the overflow entire your drain.

Why do you need a Water Butt? 

The weather can be unpredictable. Water supply from the tap can also be inconsistent. There are many reasons to use rainwater stored in a water butt instead of using tap water for your garden.

  • Convenient Source of Water

A water butt will not occupy a considerable space in your garden. It can even be a good accessory that can make your garden more beautiful. If you live in an area where tap water can sometimes be scarce, a water butt can ensure you always have water for your garden.

  • Helps Conserve Water

A water butt helps you be conscious of the water you use in your garden. You can conserve water by collecting rainwater in your water butt while keeping your garden healthy and well-maintained.

More households with water butts can save many liters of water.

  • Helps Save Money

 You pay for your water consumption. Rainwater collected in your water butt is free. Opting to use a water butt instead of your garden tap can help reduce your monthly water bill. Buying a water butt is a small investment compared to your huge savings on water consumption.

  • Plants Prefer Rainwater

Plants prefer rainwater rather than water from the taps. For thousands of years, plants have relied on rainwater, and tap water has become a new source of water.

Tap water can be dangerous to the health of your plants because of the chemicals it contains. Tap water can affect how quickly or how much your plants grow.

Water from your tap is filtered to make it safe for humans. Many chemical treatments for tap water, such as fluoride, are not safe for plants.

Tap water also often contains salt, which can be harmful to plants. Sodium is a nutrient most despised by plants. Some plants are also sensitive to chlorinated tap water.

When tap water travels through older pipes, it often picks up many substances that can be harmful to plants.

Rainwater collected in your water butt is the best option unless you want to spend more on bottled spring water. Water butts are also environmentally sustainable.

  • Reduces Flood Risk

A water butt in your garden can save millions of liters of water that can be rushing to your drains when it rains.

Rainwater going directly to your water butt reduces the volume of water that flows to the water sewer system and could relieve areas prone to water flooding.

More importantly, you will be feeling great that you are using free water in your garden. Rainwater will fall from the sky to your garden anyway, so why not collect it on a water butt.

Final Thoughts

A careful study of water butt sizes and the amount of water your garden needs are essential factors in choosing the correct garden water butt. Bigger is not always better unless you have a big garden and a bigger budget.

A point to note here is that in the USA, Colorado and Utah are the only states currently heavily regulated to stop homeowners from harvesting and using the rain that falls on their property.

Colorado allows the homeowner to store only 110 gallons of rainwater. Utah allows a registered person to keep no more than 2,500 gallons of rainwater.

An unregistered person may use no more than two containers at 100 gallons or less per container. To store more rainwater than that in those two states is illegal.


Jenny Marie

Tribal Writer


Edited By

Patricia Godwin


Patricia Godwin

Patricia has many years of experience as a content writer on various subjects, but her first love is gardening. She’s never met a plant she didn’t like and, consequently, she writes about every type of plant you can think of. Once an avid gardener with a herb garden, a succulent rockery, and a rose garden – to mention a few. Nowadays, she’s constantly on the move searching for interesting plants to bring to your attention; and explain to you all the details you need to grow, care and maintain these plants.

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