How Much and How Often Should You Water Poinsettias?

Poinsettias are the quintessential flower of the holidays. They’re a fun and easy way to level up your décor and are often gifted to us during the holiday season. Poinsettias come in an array of different cultivars with beautiful color variations. They are also known as being very beginner-friendly plants.

While their care is pretty simple, sometimes what seems straightforward is a little tricky– especially watering. Poinsettias love moisture but also hate to sit in soggy soil, so a careful balance is important to keep them in good shape through the season.

Fortunately, we’ve rounded up all you need to know about watering poinsettias. With these helpful tips, you’ll have watering down in no time at all!

The Long Answer

Poinsettias come from the large and varied Euphorbia family. The colorful bracts that many gardeners mistake for the flower itself are actually modified leaves that change color after long periods of darkness. At the center of each bract are the real flowers, which are small and yellow. These are called cyathia.

Since they’re festive plants linked with Christmas, most people discard poinsettias when they lose their leaves and color after the holidays. However, they can be kept as pretty houseplants year-round and can even be planted outside in warm climates. 

While poinsettias provide an easy floral touch to brighten up the winter, they suffer when watered too much or insufficiently. Luckily, with an understanding of their native habitat and specific needs, the process becomes much easier!

Native Habitats

Poinsettias, or Euphorbia Pulcherimma, grow naturally in the tropical deciduous forests of Central America and Mexico. They enjoy abundant rainfall for much of the year, with seasonal dry periods. The forest provides high humidity and filtered light. 

The temperature differs only about 9℉ between summer and winter, giving the poinsettias a steady growing environment with few fluctuations in heat and cold.

Short bursts of rain thoroughly saturate the plants down to their roots before rapidly draining. The soil is consistently moist but never soggy, providing a rich environment with adequate oxygen.

With knowledge of their ideal native conditions, it’s easier to understand the watering needs of poinsettias. Well-draining soil and containers with thorough, infrequent watering are key. 

How Often Do Poinsettias Need Water?

Most of us would prefer to water on a set schedule. This predictability makes us feel certain we’re taking good care of our plants and removes any guesswork. In the case of poinsettias, this would mean a thorough watering once per week. 

Unfortunately, sticking to a schedule can create problems for our plants. Poinsettias are impacted by variations of temperature, light, and humidity inside our homes, affecting how much and how often they need hydration.

Using a schedule ignores the most important factor in whether or not your poinsettia needs water- the condition of the soil. If you simply water once a week without checking the moisture content of the soil your poinsettia is growing in, you may over or under-water and harm your plant.

Rather than sticking to a schedule, check the soil every few days. Do the “knuckle-test” by inserting your finger knuckle deep in the soil. If the top layer is completely dry, it’s time to water! If you let all the soil dry out, your poinsettia will wilt and drop leaves. Conversely, if you water when the top level of soil is still moist, you risk waterlogged soil that leads to oxygen depletion and root rot.

Proper drainage is also crucial. Excess water should drain through the loose, rich soil and flow through the drainage holes at the bottom of the pot. Always remove the decorative nursery sleeve your poinsettia came in, allowing the roots to breathe and eliminating a pool of excess water. Soggy roots lead to disease and fungal infections.

Without adequate drainage, even the most attentive indoor gardener won’t be able to water appropriately. Verify that any container your poinsettia grows inside of has drainage holes at the bottom. If you choose to repot, use a houseplant potting mix with perlite or coconut coir so the water can flow freely through the loose soil particles. 

How Much Water Do They Need?

Now that you know when to water, how much water do your poinsettias actually need? Using a specific amount seems foolproof, especially for beginners. However, just as watering frequency needs vary based on your poinsettia’s soil and the conditions of your home, so does the amount of water it needs.

Instead of measuring out your water based on recommendations, you should place your poinsettia in the sink and let the water flow until the soil is fully saturated. You will know that the water has reached your plant’s roots when the excess begins draining from the holes in the bottom of the pot.

Consider technique as well. Rotate your pot so all sides are watered evenly rather than a concentrated stream on one side. You want to make sure all of the roots are hydrated, and there are no neglected pockets of dry soil. Leave the plant in your sink until all excess water flows out the bottom before returning it to its former position.

If you’ve waited too long to water, the soil may become compacted. Instead of saturating the soil down to the roots, water will run out the bottom of the container and out the sides without penetrating the soil at all. This is due to compacted soil becoming hydrophobic, meaning it resists moisture.

If your poinsettia’s soil is compacted, try watering from the bottom rather than with an overhead stream. Fill your sink with a few inches of water, place your plant inside, and let the dry soil slowly soak in the moisture through the bottom drainage holes.

This is a slow process that takes about 30 minutes. Once the soil is saturated, drain the sink and allow any excess moisture to drain from the pot. You can then replace your plant in its decorative container and chosen location. 

Factors That Impact Watering Schedules

You now know that sticking to a strict watering schedule doesn’t provide the best care for your poinsettia. Why is this? Because the environment of your home affects the plant’s needs. There are a few critical factors that influence how much and how often poinsettias need water, and keeping an eye on them will help your poinsettia thrive.

Light Levels

As decorative holiday plants, poinsettias are often placed wherever they best complement décor. They do, however, prefer specific lighting conditions, and the amount of sunlight your plant gets is a major determinant of watering needs.

Without adequate sunlight,  moisture in the soil evaporates slowly. Watering once per week in low-light conditions could cause your poinsettia to become water-logged.

In direct, bright light, plants dry out quickly. If your poinsettia sits in intense amounts of sunlight, you may need to increase watering to more than once per week.

Ideally, poinsettias will get 6-8 hours of bright, indirect light per day. Once you’ve found a good spot for your poinsettia, check the soil every couple of days to determine how often the top level dries out. Water only when this layer is thoroughly dry. This way, you will water when your plant actually needs it, responding to the particular lighting conditions of your home.

Temperature

Temperatures in your home also influence watering frequency. Poinsettias prefer a warm climate, between 65-75℉ to flourish. But considering that their modified bracts display their trademark color during the chilly days of winter, it’s likely that your holiday poinsettia will experience some temperature fluctuations!

Hot indoor air or placement near heat sources in the home will cause the soil to dry out quickly. If you want to ensure your poinsettia is getting sufficient water in this environment, you’ll need to check the soil daily. 

Bursts of cold air from open windows and doors will negatively affect your poinsettia, while consistently cool temperatures will slow evaporation in the soil. You will need to water less frequently if your poinsettia is kept below 65℉. Again, let the soil itself be your guide, and you will know the right time to water.

Humidity

True to their tropical nature, poinsettias appreciate some humidity. Ideally, the moisture content in the air should be between 55-75%. However, the air in our homes varies greatly, which impacts the amount of water your poinsettia needs.

In low-humidity environments with hot, dry air, poinsettias will retain less moisture in the soil. Check them often and be sure to water every time the first few inches of soil are completely dry. You can also use a humidifier to boost the moisture in your home, reducing the need for frequent watering.

If you have high humidity, the poinsettia’s soil will hold onto moisture for longer periods, decreasing how often you need to water. Testing the soil will tell you when your poinsettia needs water, preventing overwatering and rotted roots.  

Signs of Overwatering

If you follow a schedule rather than the condition of the soil, you are likely to over or under water your poinsettia. Overwatering is easy to do, and a common culprit for the death of holiday poinsettias!

Poinsettias love moisture, but this doesn’t mean they like consistently wet soil. Heavy, sopping wet soil deprives your plant of oxygen, causing it to suffocate or develop fungal issues.

Overwatered poinsettias will have wilted, yellowing leaves, which eventually drop from the plant. Under the soil, the roots will rot, becoming soft and diseased. They will no longer absorb moisture and nutrients..

If you see these symptoms and suspect you’ve been overwatering, allow the soil to dry out thoroughly before watering again. If your poinsettia continues to wilt, remove any affected leaves and try repotting with fresh, well-draining soil. When transplanting, trim off any rotten roots to prevent fungal spread. Use a container with lots of drainage holes, and watch your plant carefully as it recovers.

Signs of Underwatering

Poinsettias also struggle when underwatered. You will notice wilting, brown-edged or yellow leaves that curl up at the ends. The wilting in this case is caused by insufficient water inside the plant’s cells, damaging its internal structure.

As with most issues, the soil is key to understanding your plant’s needs. If the soil in the poinsettia’s pot is dry and compacted, it hasn’t received enough water and will need intervention to stay alive.

Treat this problem immediately by watering from the bottom, allowing the roots to drink up through the drainage holes in the pot. If the roots are not irreparably damaged, the plant will respond by perking up within an hour or two.