By Lori W-greenhouse manager
The change of seasons are most appreciated by a greenhouse grower because it means the start of a different crop to grow. “The poinsettias are hereâ€¦!” Those are 4 words that bring much excitement and trepidation to the grower. Poinsettias are one of my favorite plants to grow. Just to give you an idea of what it takes to produce that beautiful Christmas plant, I’ll give you a short itinerary of the growing process:
Mid August: Poinsettia plugs arrive. They are shipped in a box from an out of state grower. The plants are only 1 Â½ -3 inches tall and are started as cuttings and rooted into a foam-like material. The plugs are separated by color (red, white, and pink) and planted into 6 Â½” pots. Some have 3 plants per pot and some have 4 . My favorite is the tricolor where we put one of each color in a pot. They are watered in with a specially formulated poinsettia feed.
Poinsettias, as with all plants, are prone to certain diseases, fungal infections and pests so we are meticulous about preventative treatments. The plants get regular fungicide treatments and beneficial insects are used to scout out and eliminate the “bad” insects that can be a nuisance to poinsettias. This avoids having to spray pesticides. Some “bad” insects can just be annoying but others can cause physical damage to the tissue. Others can transmit diseases.
The poinsettia grower is busy checking the watering daily, applying fungicides monthly and beneficials weekly. Poinsettias also require calcium to produce strong plants and bracts( the flower), very similar to humans, and like humans we can’t always get enough in our diet so we need to take supplements. Poinsettias get their supplements by absorbing calcium through their leaves which is sprayed on the plants weekly.
Next in the itinerary, about 6 weeks after transplanting the plug, the plants get stripped of their side shoots. It is normal for a poinsettia plant to send out side shoots out of each leaf node on the stem. In most cases the side shoots are left on to produce a multitude of flowers per plant. Our goal for some of our crop is to have 3 or 4 distinctly larger blooms in a pot. The side shoots are stripped off so all the energy goes to the single flower. It’s a time consuming task being careful not to take leaves off or disturb the growing tip.
Spacing is also very important. As soon as the leaves from 2 plants touch, the rows are adjusted to allow for good air circulation between the plants and for getting uniform light. Sometimes if there is a stretch of dark rainy days, typical of fall weather , the poinsettias will get a growth spurt similar to “leggy” seedlings when there’s not enough light. To help slow down this growing process and keep them shorter and stocky, a chemical called a plant growth regulator(PGR) is applied by the grower. This treatment may be applied up to 3 times to keep the plants compact.
The color of the bracts is controlled by the light and length of day. The grower really can’t control this natural process other than getting the plugs planted at the correct time. By late November the top leaves, (bracts ) start changing color and will be in their full glory just in time for the Holiday Season.
So this Holiday Season when you pick out that perfect poinsettia as a gift or purchase it for your Holiday decorating, keep in mind the hours of attention and special care the growers here at Chester’s provided to nurture that plant into a beautiful poinsettia.