How to Care for a Poinsettia Until Next Christmas

Check the plant for pests (most pests won’t develop on plants grown in greenhouses, but they can appear within just 2 weeks of being indoors). If the plant is infested, it’s best to discard it and purchase a new one to care for until next year.

If you still wish to keep a particular plant, you can use soapy water to spray the plant and soil multiple times to eliminate pests. Mealybugs are often the biggest issue and can be treated by dabbing them with a cotton swab dipped in alcohol. However, this must be done before the infestation spreads beyond control.

Place the plant in a cool (not cold) room with filtered sunlight and reduce watering. Allow the soil to dry between waterings or water sparingly (overwatering is the leading cause of indoor plant death during winter when the plant is less active and not absorbing nutrients as usual. Overwatering can lead to waterlogging, mold, root rot, and yellowing leaves). When nighttime temperatures rise above 10°C, you can move the plant outdoors.

Decide on the shape you want your plant to have by Christmas. If you prefer a small, bushy plant, trim the entire plant to about 10 cm above the main stem. For a larger plant, simply pinch off the tips of each main stem and continue doing so until around July. To shape the plant, remove all branches except the tallest, straightest main stem, and avoid pinching the top, only trimming side shoots throughout the season.

Avoid placing the plant in full sun initially. Direct sunlight can cause sunburned leaves, leaf drop, or even kill weaker plants. Start by placing the plant in full shade, then move it to partial shade for two weeks, and finally to full or partial sunlight for the rest of the season. This helps the plant harden and adapt to outdoor conditions.

Begin watering the plant regularly. Fertilize after every 5 waterings or every two weeks (whichever comes first) using poinsettia-specific or indoor plant fertilizer. If desired, you can use diluted evergreen fertilizer to encourage new leaf growth (at this stage, focus on foliage rather than flowers).

When it’s time to bring the plant indoors in the fall, start the process of turning the plant’s tips red (or pink, or whatever color it was last winter). This process can take up to 2 months, sometimes longer, depending on environmental conditions and the type of plant.

• Switch from nitrogen-rich fertilizer to indoor plant fertilizer or poinsettia-specific fertilizer, and reduce the frequency of fertilization by half.
• Begin the long-night/short-day cycle necessary for budding: 13 hours of continuous darkness and 11 hours of bright sunlight daily. Maintain nighttime temperatures around 15°C. Rotate the pot regularly for even light exposure. (Note: Complete darkness is crucial – even streetlights or passing car lights can disrupt budding.)
• Stop the light/dark cycle after about 2 months and place the plant in the sunniest window indoors. Reduce fertilization and avoid overwatering!

Move the plant outdoors if possible. Depending on your climate, poinsettias often thrive better outside, so relocate the plant to a spot with partial afternoon shade. Excessively hot and dry weather can slow growth.

Don’t expect the plant to look store-bought. Your plant will never resemble the ones sold in stores, as those are typically young plants. To achieve a store-bought appearance, take cuttings from the parent plant (don’t worry, the parent plant will still flower) from late April until you bring it indoors to encourage blooming. Rooting hormone can be used, but poinsettias often root well in compost (such as garden compost made from grass clippings).

Focus on timing the flowering. When you want your poinsettia to bloom fully and how you plan to care for it afterward will determine when to start the flowering process. For Thanksgiving blooms, begin by October 1st, and start by Halloween for Christmas blooms. You can start earlier, but you’ll need to maintain the light/dark cycle to keep the plant flowering throughout the season.

Place the plant in a dark room, closet, or cabinet. Choose a location where no light can enter.

Use warm white CFL or warm white fluorescent lights. You need "warm white" light instead of regular grow lights, as the plant requires red light for flowering in addition to timing.

• Ensure sufficient light is provided. A single 26W CFL bulb (equivalent to a 100W regular bulb) for two or more plants is insufficient. Use one 26W CFL bulb per plant, hanging 30-50 cm above the plant. Make sure the light height is adjustable, as the plant grows rapidly during flowering.
• High-pressure sodium (HPS) lights can also be used. However, be cautious, as authorities might mistake your setup for growing another plant with similar light cycles! HPS lights are often associated with illegal plant cultivation.

Set a schedule. Standard office hours (9 AM to 5 PM) work well. Do not disturb the plant when the lights are off. While 14 hours of darkness is considered sufficient, 16 hours is always better (with warm white light).

Look for signs of flowering. The first signs of budding are the top leaves turning red as the plant senses the arrival of autumn. Keep the plant under light until it blooms.

• You can leave the plant in the nursery throughout the season and only bring it out for the holiday you wish to display it.
• The nursery is also ideal for other plants you’ve purchased this year, as they will produce healthy cuttings for propagation, so place them all in the nursery.

Avoid exposing the plant to more than 10 hours of light per day. This helps prolong flowering after the season ends. Care for the plant diligently: water properly, prevent pests, and provide ample light during its daytime cycle. With proper care, poinsettias can bloom even after Mother’s Day!

• If the plant continues to flower too long, expose it to 24 hours of light to trigger a dormant phase. Some plants may still produce buds when placed outdoors during summer.