How Long Can Perennials Go Without Water?

Every gardener knows that watering plants is essential to their survival. However, to avoid overwatering and use resources in a smart, eco-friendly fashion, you may be wondering how long it’s safe to let plants such as perennial flowers go without water.

Generally, perennials require about an inch (2.54cm) of water per week to be healthy. Still, the specific type of flower, soil, and weather conditions may influence the amount of water needed.

Want to get more guidance on how much water you should provide for your perennials? Below, I’ll provide you with useful information on the best practices for watering this type of flower so you can keep your garden looking its best.

What Is the Best Timing for Watering Perennials?

Deep, less frequent watering helps your perennials develop long and strong roots. In contrast, if you water your perennials too frequently, it may cause them to develop spindly roots that don’t run deep into the ground.

The best way to determine when it’s time to water your perennials is to check the soil the flowers are planted in. Use a trowel to dig about three to four inches (7.62 to 10.16cm) into the soil next to the growing plants. If the soil has dried out and retains little moisture, your plants might benefit from additional watering.

Some plants also give clear signs that they need more water. For instance, tulips will begin to droop when they lack hydration. If you notice that your flowers aren’t standing as tall and straight as they once did, adding water may help alleviate the problem.

How Do Plants Use Water?

Plants use water for photosynthesis, the process by which plants use energy from the sun to create food to sustain themselves. Water is an essential component of photosynthesis and plants combine hydrogen in the water with carbon dioxide from the air to sustain themselves.

Oxygen is given off as a byproduct of the process of photosynthesis, giving us the breathable air we need to survive. Read more here for more information about how the photosynthesis process works.

What Time of Day Should You Water Perennials?

It is best to water your perennials in the early morning. This gives the plants enough time to soak water in through the roots before moisture is lost to the hot afternoon sun through evaporation.

Another benefit of watering early in the day is that any excess water that settles on the foliage will evaporate before it has time to settle for too long. This will help prevent mold formation and other moisture-related problems. 

Watering at midday is not desirable. It causes a good portion of the water to evaporate before your plants have had the chance to soak it in and use it for photosynthesis. The increased wind speeds at this time of day can also disperse water, causing the distribution throughout your garden to be uneven.

If your schedule doesn’t allow you to water plants early in the day, watering in the late afternoon or early evening is a good alternative. Just don’t water them too late in the evening, as this won’t leave adequate time for the foliage to dry off before night falls.

More Tips on Watering Your Flowers

Want more pointers on the best practices for watering the perennials in your garden? Follow the below advice to help your plants thrive to their fullest potential.

Hand Watering Your Perennials

Watering by hand can be a relaxing way to care for your garden. It also helps you ascertain that your plants are getting the water they need since you gave it to them personally. Apply water to the base of the plant so that it can soak through to the roots where it gets absorbed into the plant.

You can get a watering spray wand to make hand watering easier and more efficient. Most spray wands come with adjustable flow, allowing you to control the amount of water you’re using and apply the water gently such that it doesn’t damage your plants.

Using Sprinklers in Your Garden

Sprinklers are a convenient way to automate your garden’s irrigation process. However, there are a few pitfalls associated with this watering method. For one, the droplets sprayed into the air may evaporate or get taken up by the wind before they have a chance to reach your plants. Sprinklers can also lead to overwatering if you aren’t implementing them properly in your garden.

To avoid overwatering, set up a rain gauge or a marked container when you have your sprinklers running and measure how long it takes for a half-inch of water to accumulate. You can then attach a timer to your hose. The timer will allow you to set the correct amount of time your sprinkler will be running, so you don’t oversaturate the soil.

Choosing the Right Soil

While it may not seem directly related, the type of soil you plant your flowers in is essential to watering them properly. Dense clay soil retains water for a long period of time, becoming sticky and moist when it’s saturated. By contrast, sandy soil is loosely-packed and quickly drains any water that runs through it.

The ideal soil conditions vary depending on the type of flower you’re planting. Soil that retains too much water can create overly-moist conditions for perennials that grow from flower bulbs, causing the bulbs to rot or mold to set in. However, quickly-draining soil may not give certain plants enough time to absorb the water they need before it drains away. Therefore, knowing the needs of the specific flower you’re planting is essential.

If you need to improve the drainage of your soil, adding a layer of grit or sand to your soil can help. This is especially helpful with dense loamy or clay soil if you’re planting flowers that thrive better in loose soil.

Different Perennials and Their Watering Needs

There are many different kinds of perennials out there, each with its own requirements regarding what they need to grow healthy and strong. Here are some of the most popular types of perennial flowers and some tips on how to water them.


Daffodils are flowers that bloom in the early spring, bringing some of the first colors of the season to your garden. When cared for properly, you can anticipate your daffodils sprouting again every spring.

Daffodils require plenty of water. You should thoroughly water the ground you plant your bulbs in when you first put them into the ground. Continue watering for about three weeks after the flowers begin to bloom, then stop the watering. The flower will conserve energy in the bulb for next season’s growth.


With their unique shape and the vibrant array of colors the different varieties of this flower offer, tulips make an excellent addition to any garden. These flower bulbs will come back year after year if offered the correct conditions, giving you a sight to look forward to every spring.

Tulips should be watered once per week. They need roughly two-thirds of an inch (1.69cm) water to get the energy they need for photosynthesis. Be certain to water them in late winter and early spring to help them develop for the start of the season. These flowers require little supplemental watering once they’ve grown, but you should help them out with a bit of extra water if drought conditions occur.


The large globes of flowers that are characteristic of hydrangeas make a stunning display that adds great appeal to any garden. The different varieties of this flower show off a wide array of colors, letting you choose the one that best fits the look you’re going for.

Hydrangeas are another perennial that requires plenty of water. They should receive one inch (2.54cm) of water per week throughout their growing season. You also need to water them deeply, at least three times a week to encourage strong root growth.


An inch (2.54cm) of water per week is a good guideline to follow for your perennials. Applying the water deeply and less frequently will encourage strong root growth, helping your plants get the energy they need for photosynthesis.

Establish the watering method that works for you and adjust according to the exact flower you’re growing. With the right tools and knowledge on your side, your garden will be flourishing in no time.

Alexander Picot

Alexander Picot is the principal creator of, a website dedicated to gardening tips. Inspired by his mother’s love of gardening, Alex has a passion for taking care of plants and turning backyards into feel-good places and loves to share his experience with the rest of the world.

Recent Posts