It is Christmas in July for the greenhouse producers who grow poinsettias. In order to have plants that are blooming for December sales, greenhouses start the process early. Poinsettias require months in the greenhouse before they are ready to be purchased and taken home.
Leanne Pundt, one of our Extension educators was scouting the plants for whitefly immatures at one the Connecticut growers last week and took these photos.
Wholesale growers across Connecticut started shipping poinsettias in mid-November. Poinsettia are a long-term crop, started from rooted cuttings in early to mid-July. Plants are pinched to promote branching and growers measure the height of the plants on a weekly basis, and enter data into a computer program, to make sure the plants will be at the desired height for their customers. These particular poinsettias were grown using biological controls. Whiteflies can be a troublesome pest for poinsettias, because homeowners can object to even one whitefly on a plant. Using biological controls, growers regularly release a small mini-wasp, Eretmocerus eremicus that parasitizes the whitefly nymphs. In the photo at left, you can see pupae glued to paper cards. Growers also release a predatory mite, Amblyseius swirskii that feeds upon whitefly eggs and nymphs. Biological fungicides are also used to prevent root rot diseases.
Poinsettias (Euphorbia pulcherrima) are originally from Mexico. In the 20th century, the Ecke family of California was
instrumental in the development of the poinsettia as a potted holiday plant. Today, there are hundreds of compact, long lasting cultivars. Red continues to be the most popular color, however, white, pink, and specked or marbled varieties also sold. The flowers of the poinsettia are the small, cup-like structures at the center of the showy “bracts” which are modified leaves.
Retail Care Tips
Place plants in a sleeve to protect them from temperatures below 50° F when bringing your plant home. Be careful not to overwater your plants, they are very susceptible to root rots. Place poinsettias in a bright, sunny location away from hot or cold drafts. Poinsettias are not poisonous, but their milky sap can irritate the skin. December gardening tips are available from the UConn Home and Garden Center.
As we decorate our homes for the holidays with cheery plants, evergreen boughs and berries, it is important to take into account which plants and materials might be toxic to young children and pets. Many plants can pose serious threats to the curious two year old or inquisitive dog, cat or bird.
According to Botanic Gardens Conservation International, there are approximately 400,000 known species of plants inhabiting the earth. Of these, only about 700 species found in this hemisphere are know to cause loss of life or serious illness in man or animals. The toxicity of many new, exotic houseplants and garden plants is not as of yet known. Also be aware that even ‘safe’ plants may cause problems as the plant or soil may be contaminated with pesticides and/or growth regulators. If your household contains young children or curious pets, you may want to consider purchasing plants from an organic grower or placing them out of reach.
Not all plants listed on poisonous plant lists are fatal. Plants are labeled as poisonous if they cause any kind of problem to humans, farm animals or pets. Some are extremely toxic. For example, two oleander leaves will prove fatal to an adult. Other plants may just cause minor skin irritations.Most toxic plants are bitter to the taste or irritate the mouth so generally the animal or person stops eating or chewing on it long before enough is consumed to cause any toxic effects.
Let us look at some common holiday plant materials and their toxicity. First, let me dismiss the rumor concerning poinsettias. They are not the deadly plants they have been made out to be. However, they do contain a white, latex-like sap. Some people are allergic to this sap and a contact dermatitis may result. If eaten, they may cause injury to the digestive track.
This morning’s winter weather reminds us to check in on our gardens and house plants as well. Here are some helpful tips for your winter gardening needs:
Tap the evergreen branches gently to remove snow and prevent the branches from breaking.
Check fruits, vegetables, corms and tubers that you have in storage. Sort out any that show signs of disease and dispose of them.
Houseplants may need to be watered more often when the heating system is on.
Amaryllis bulbs may be started now. If they are established bulbs in old pots, two inches of soil should be removed from the surface and replaced with a good, rich mixture.
Deck the Beds – For those who have a real Christmas tree, recycle it after the holidays are through. Cut off branches and use them as insulation over perennials. In the spring, chip or shred the branches to create mulch or add to the compost pile.
Although many see it as a safer alternative to salt, resist using fertilizer to melt ice. This creates nitrogen runoff issues that could damage local bodies of water. Try using calcium chloride, sand or kitty litter instead.
Continue to harvest Brussels sprouts. They’ll typically keep even when buried in snow drifts.
Display poinsettias away from heat sources and cold drafts. Keep soil consistently moist, but not soggy. Poinsettias that dry out droop dramatically and drop their flowers.
Don’t walk on frozen grass, especially if there is no snow cover. Without the protection of snow, grass blades are easily broken causing die-back in your lawn.
If you have friends or family that like to garden, think of gardening gifts for the holidays. Books, gloves, hand tools, weather instruments, and fancy pots are some fun ideas to consider!