How to water plants while you're away

Except if you have a friend, neighbour or even a gardener to keep an eye on your house plants or vegetable garden while you're away, an automated or self-watering system will be your best bet. Luckily, there's a system to match every situation, budget and gardener! From watering globes to sprinklers, we'll take you through all the different solutions to keep your plants watered when you're not around.

Self-watering systems

Watering stakes and globes

Watering stakes and globes are designed to meet the individual watering needs of each plant to keep all your plants healthy and happy. Made of plastic or ceramic, both stakes and globes feature a hollow stake which sinks into the soil of a pot or planter. These systems are designed to allow the water to gradually infiltrate into the pot to keep your plant hydrated using a built-in or external water supply.

Globes contain their own supply of water while stakes will need to be screwed into a bottle of water. The amount of water provided by watering stakes and globes is limited by the size of the globe, bottle or container you use. Nonetheless, this system is practical, ecological and inexpensive. It's also possible to adapt the system to the needs of your plants as each container can be fitted with its own watering stake or globe.

These devices go by a range of different names including bottle top watering spikes, self-watering spikes and slow release watering globes. Here is a rough guide on how far you can expect your water to go:

• 3 days with a 30 ml supply;

• 7 days with a 50 ml supply;

• 21 days with a 1.5 litre supply;

• 28 days with a 2 litre supply.

Tips for using watering globes or stakes

Test your equipment before you leave to check how long the system lasts and to monitor the amount of water being released to the plant.

Indoor drip irrigation

Amateur botanists or anyone with a lot of plants around the house might prefer to invest in an indoor drip irrigation kit. More accurate than a globe or stake, this system involves fitting each pot with an adjustable drip head. Indoor drip irrigation can be connected directly to a tap or a large container of water for an unlimited supply of water.

While these systems look a lot more complex, they are just as easy to use as more basic equipment. However, they can be expensive. An indoor drip irrigation kit will include:

• drip heads;

• a pipe which can vary in length (with the possibility to extend if required);

• a timer.

Depending on the layout of your home and where you intend to connect the system to the water you might need a tee connector to divert your mains supply. Indoor drip systems will generally require the use of an adapter designed to fit your tap. If you don't want to use mains water, it is usually possible to connect these systems to a water container or even a water butt.

Holiday watering kits

A really handy solution for pots and planters, holiday watering kits come with everything you need to water over 30 plants. These kits are designed to be connected to a tank which can vary in volume. The flow rate of the emitters or drip heads can be adjusted to meet the needs of each plant. The pump used to direct the water into your plants can be plugged into a standard socket. Holiday watering kits can be used indoors and outdoors and are ideal for keep multiple balcony or patio plants watered when you're on holiday. What's more, they're easy to install!

Tips for using a holiday watering kit

Don't wait until the day you leave to set up the system and test all the watering cycles offered by the programmer. Otherwise you run the risk of watering too much and drowning your plants or not watering them enough – in which case you'll be greeted by shrivelled plants on your return!

Sprinklers

Lawn sprinkler systems are some of the easiest irrigation systems to set up.You will need the following equipment:

• one or several oscillating, fixed or rotating lawn sprinklers;

• a hose of the correct length and diameter;

• as many quick (or tee) connectors as you have sprinkler heads;

• the right tap connectors to attach your garden hose to your garden tap;

• a timer.

How to pick the right sprinkler heads 

Your choice of sprinkler heads (i.e. whether you go for oscillating, rotary or fixed sprinklers) depends on the size of your lawn. They must be set out to cover your lawn evenly and in full. To do so, you will need to pay attention to the following:

• the maximum surface in m² that the sprinkler can reach;

• the number of modes or cycles offered by the sprinkler system;

• the water flow rate and pressure required by the installation (measured in litres per minute and bars, respectively).

Underground irrigation: a more permanent solution

Underground irrigation systems are made up of a series of buried pipes and an automated timer system that requires the installation of valve boxes. This type of irrigation is more complicated and costlier to install and means you will have to dig trenches measuring around 25 cm in depth all over the garden. You will also have to carefully calculate the system requirements in terms of water flow rate and pressure.

The last system we're going to tackle is vegetable garden irrigation systems. These systems fall into two main categories: above ground irrigation and underground irrigation. However, a combination of both will usually work best. For example, ornamental gardens, vegetable gardens, flower beds, rock gardens and potted plants should ideally be watered via drip irrigation to ensure each plant is properly catered for. However, if you also have a lawn or fairly easy-going plants, an above ground installation, such as a sprinkler system, will work best. That said, you might get away with only using sprinklers as long as you place your pots and planters strategically around the garden. However, this does depend on the design of your outdoor space. Bear in mind that this method won't work for flower beds or vegetable patches.

Alternatively, a soaker hose can be a good option for flowerbeds, rock gardens and small kitchen gardens. These hoses can be connected to an automated watering circuit or may be equipped with their own timers. 

All of the following equipment can be used to garden irrigation system buying guide">water a vegetable garden:

• oscillating, fixed or rotary sprinklers;

• drip irrigation;

• soaker hoses (partially buried underground).

When to water your outdoor plants

Ideally, you should always water late in the day once the sun has gone away or in the morning provided the nights are cool enough. As you will be setting to your system to work while you're not there, it's best to program it for very early in the morning – unless you're expecting a heatwave! You can also set up more than one system to meet the needs of different plants or areas.

These days, everything is 'smart' and your irrigation system is no exception! Here are two examples of smart watering technology.

1. Automated watering systems with humidity meters (or hygrometers) to pause watering when it is raining or just after rainfall.

2. Bluetooth- or Wi-Fi-connected watering systems so you can manage your garden or vegetable garden directly from your smartphone!

More information

• Watering lance and spray gun buying guide

• How to harvest rainwater

• Rainwater harvesting system buying guide

• Submersible pump buying guide

• Surface pump buying guide