Plants can’t grow without water! Here are some guidelines on how much and the best ways to water your garden.

How much water does my garden need?

There is no universal answer to this question, but a good rule of thumb is that a vegetable garden should receive 1 inch of water per week (or 62 gallons of water per 100 square feet per week). This means that the total amount of water your garden receives from rainfall and waterings should add up to about 1 inch of water per week. Use a rain gauge to keep track of how much water your garden is receiving.

However…

There are a few factors that influence how much water your specific garden may need.

Soil Type – There are 3 basic kinds of textures soil can have: sand, silt, or clay. 

  • Sandy soil is porous and allows water to drain through quickly.
  • Silty soil does not allow water to drain as quickly, but holds onto less water than clay.
  • Clay soil is more compact than the other soil types and holds onto water very well.

 If your garden’s soil has a high sand content, you may need to give your garden more water. Alternatively, if your garden’s soil has a high clay content, you may want to use less water. We recommend getting a soil test done so you know what kind of soil you have in your garden.

Temperature – High heat can cause plants to dry out, and more water may be necessary to keep them in good shape. If you are going through a heat wave, you may need to give your garden more water than usual to prevent dehydration.

Humidity – Humidity affects the ability for water to evaporate. In high humidity, water will take longer to evaporate from the soil, and you may want to reduce the amount of water given to your garden. In lower humidity, more water may be necessary.

Type of plant – All plants are different, and will therefore grow best under different conditions. Plants producing large fruit like watermelons are going to require more water than plants like basil. Make sure to do some research to find out how much water your plants need.

When should I water my garden?

The best time of day to water your garden is early in the morning. The temperature is cooler in the morning, which means less water will be lost to evaporation while you are watering. Also, any leaves that get wet will have time throughout the day to dry off, reducing the risk of developing diseases or growing fungus.

If you cannot water in the morning, watering in the evening will still have the benefit of conserving water compared to watering in the peak heat of the day. However, if you choose to water in the evening, it is important to water only the soil and not the leaves of your plants. Allowing wet leaves to sit overnight will increase the risk for your plants to develop diseases or grow fungus.

How often should I water?

It is unnecessary and can even be harmful to water your garden too frequently. Again, there is no universal answer to this question, but in general, watering about 1-2 times per week is likely to be ideal for many gardens. By watering your garden less frequently with deeper waterings, rather than watering very frequently with light waterings, you will help your plants grow deeper and stronger roots, making them more resilient to harsh-weather conditions.

How should I water my garden?

When watering, avoid wetting stems and leaves. The goal of watering is to get the water through the soil to the roots of your plants. Watering just the soil near your plants will reduce the risk of your plants developing diseases from wet leaves, and will help conserve water, as less water is being sprinkled needlessly over the tops of your plants. You can also avoid watering areas in between plants, reducing the potential for weeds to grow. Make sure to water with a gentle trickle/stream (think of how water comes out of a watering can) rather than a powerful spray.

You have several options when it comes to watering equipment, including:

Soaker hoses

Drip irrigation

Basins

Sprinkler

Watering by hand

Final thoughts

Nobody knows your garden better than you. Pay attention to the way your plants look and the conditions they are in. Are your plants wilting or shrivelling up? Has it been raining more than usual lately? If you notice signs of stress in your garden, do not wait to address them. Ultimately, you and your garden’s community are the ones who will know the best way to water in your garden.

Finding a Water Source 

A crucial part of setting up your garden space is having a water source. For many gardens this looks like a typical garden hose ran off of spigot on a building. If your garden doesn’t have easy access, you will need to explore other options to get water access. This may be putting in a new water line that extends directly to your garden. Depending on the distance, this can cost as high as $3,000. For many projects near buildings, however, the cost can be lower into the hundreds. 

If your garden space is near a fire hydrant, you may be able to work with the city to get a fire hydrant key and hook the hydrant up to a garden hose. How this relationship works is different in every location, contact your local representative (normally mayor or alderperson) to find more information on how this works. 

Rainwater collection is another attractive option for gardens, but comes with its own set of issues. For example, if there is a drought and you do not have a back-up water source, you run the risk of losing your crop for the season. Depending on the collection method, the rainwater may be safe for direct to soil watering only, and not widespread watering that could get on the leaves or produce. We recommend rainwater harvesting only if there is a feasible backup. 

Unfortunately, if water access is a major issue, it may also be time to reconsider the growing space. In most cases, you should be able to run a line directly to your garden. Even if this ends up costing a bit more than you would like, it is a one time cost that is crucial to your garden’s success.