Poinsettias need the top inch of soil to dry out between bouts of watering. Water poinsettias with a good soak, so that water emerges from the drainage holes of the pots. Typically, watering poinsettias with generous soak once a week meets the plants moisture requirements, without causing root rot.
It is important to know how often and how much to water poinsettias as they are sensitive to over watering and under watering.
Keep reading to learn how to establish the optimal watering frequency for your climate and the conditions in your home…
How Often to Water Poinsettias
Poinsettia are shrubs that are native to Mexico and central America where they grow in tropical regions with some humidity, warm temperatures and occasional rainfall.
Poinsettia are well adapted to the conditions of their native habitat which transfers quite well to growing as house plants, but they are sensitive to both over watering and under watering, preferring the soil to dry out a little bit between watering rather then consistent moisture or damp soil.
To grow poinsettias in the home it is important to recreate the watering conditions and cycle of soil moisture as their native environment.
Poinsettias require a generous soak followed by the top inch of the soil to drying out somewhat between watering. Typically this means watering poinsettias once a week to stay healthy and avoid root rot.
It is important to know there are several factors for how often to water poinsettia, as the rate at which the soil dries out can vary in different climates and home conditions such as…
- The natural humidity of the climate (humidity reduces water loss from the leaves and slow evaporation from the soil which can mean you water the poinsettia less often).
- The size of your pot (smaller pots dry out much quicker).
- Whether the poinsettia is in the current of air con or forced air or any draughts (air currents can sap moisture from the leaves and increase the poinsettias demand for water).
- The capacity of the soil to retain moisture.
To establish how often to water your poinsettia in your home feel the soil to see if you can detect any moisture.
If the soil is moist then delay watering for a day or so but if the soil feels somewhat dry to a depth of one inch this is the perfect time to water.
This cycle of watering is the optimal balance of moisture for poinsettias for a healthy plant and to avoid the affects of under watering and over watering.
This also mimics the watering cycle of its native environment.
Note that using a spray bottle to mist the leaves of your plant once a week or so helps to emulate the more humid conditions of the poinsettias native range.
Poinsettias should be watered consistently throughout the year but note that demand for water can fluctuate if, for example in Winter the heating is on more frequently as this can dry out the pot quickly.
Adjust your watering frequency throughout the year if necessary but always let the top inch of the soil dry out between watering to avoid root rot and maintain a healthy plant.
How to tell if you are over watering or under watering poinsettia…
If your poinsettia is over water or under watered the leaves turn yellow and start to droop, therefore it can be quite difficult to make the distinction between an over water of under watered plant just by appearance.
However poinsettias suffering from drought stress tend to have somewhat more shriveled, wilted or curled leaves which can drop off in reaction to drought compared to plants suffering from too much watering.
The easiest way to definitively tell the cause of leaves turning yellow is to feel the soil. If the soil has dried out completely then give your poinsettia a really good soak.
Ideally place the plant pot in a basin of water for around 10 minutes to allow the water to properly infiltrate the soil so the roots can uptake the much needed water.
If your poinsettia appears to be over watered and the soil is too moist then scale back the water so that the top inch dries out.
Over watered poinsettias are more difficult to revive then under watered plants due to the increase risk of root rot which causes a poinsettia to die back.
(Read my article how to revive a dying poinsettia plant).
How Much to Water Poinsettias
Knowing how to much water to use when watering poinsettias is essential for their care.
The variability of the climate and conditions in the home can all influence how often to water poinsettia but the amount of water should stay the same regardless of conditions.
Water poinsettias with a generous soak so that excess water trickle out from the base of the pot.
This ensures that the water has infiltrated the soil sufficiently so that the roots of the poinsettia can uptake the water they require.
A really good soaking also encourages the roots to grow and establish in the soil for a healthy, more resilient poinsettia.
Watering too lightly results in only the top inch or so of moistening the soil and the water does not infiltrate to the roots of the plant where it is needed which can even lead to drought stress.
Watering with a good soak then allowing the soil to dry recreates the cycle of rainfall, followed by a period of dryer weather in its native habitat to which the poinsettia is adapted.
Water Poinsettias in pots with Drainage Holes in their Base
Poinsettias do not tolerate their roots being in damp soil so it is important that your pot has drainage holes in the base to allow excess water to escape.
Watering so that water emerges from the base of the pot is the best way to ensure that you have watered your poinsettia with enough water.
If your poinsettia is in a pot without drainage holes the base then water pools around the roots and the poinsettia dies of root rot.
Too much water can still pool around the roots and keep the soil damp if…
- Saucers and trays are underneath pots. People often use saucers or trays to prevent water from spilling in their home after a bout of watering. It is essential that you empty the pot regularly otherwise the standing water prevents the soil drying out sufficiently for the poinsettia and the plant dies back.
- Roots and compacted soil in the drainage holes. If you notice water draining slowly from your poinsettia then check to see if the drainage holes are clear so that water can escape properly to prevent root rot.
- Decorative outer pots. Poinsettias are commonly sold in plastic pots with drainage holes but presented in decorative outer pots for sale around Christmas time. The outer pot can prevent water escaping properly and the soil stays saturated which causes root rot so either empty the outer pot of water regularly or use a saucer or tray and plant poinsettia in a pot with drainage holes.
(Read my article, why is my poinsettia dropping leaves?)
- Always wait for the top inch of soil to dry out before watering poinsettias to meet the watering requirements and avoid root rot. Water poinsettias with a generous soak so that water trickles from the base of the pot.
- Typically watering once per week is suitable. Adjust the frequency of watering to suit your conditions.
- Poinsettias should be planted in pots with drainage holes in the base to allow excess water to escape and to avoid root rot.
- The symptoms of an over water and under watered poinsettia are the leaves turning yellow and drooping. Under watered poinsettias also drop leaves.