Holiday Plant Care

Poinsettias, Amaryllis, and miniature Christmas trees make delightful gifts during the holiday season, but they need special care to last. 


Two plants couldn’t be more different than poinsettias and miniature pine trees, and their care is equally different. In each case, if these plants are simply set on a shelf or counter top and watered occasionally, they will probably never make it to the end of January. Amaryllis plants are often watered to death. Being bulbs, your holiday Amaryllis can last for several years, given the proper care.

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Stone pine

Red & white poinsettias

Amaryllis

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Poinsettias
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Poinsettias (Euphorbia pulcherrima) are fascinating plants. The bright red blooms we see are actually leaves and the plant itself is a tree that can reach 13 feet in height! The red parts are bracts, or modified leaves. The flowers of poinsettia plants are tiny structures hidden away in pseudo flowers called cyathia. Native to Mexico, poinsettia plants need 12 hours of darkness for at least five days in a row to turn from green to red, in a process called photoperiodism. Even the slightest exposure to sunlight, street lights, headlights, or lamp light will interfere with this process. To keep poinsettia plants healthy indoors, find a spot with strong morning sun and afternoon shade. Poinsettias can be grown outdoors, in the Bay Area, as long as they are protected from frost. Commercially grown poinsettias are infected with a phytoplasma (bacteria) that causes the plant to produce abundant auxiliary buds, which make the plant grow in a more bushy structure. Poinsettias left on their own have a more open, spindly growth. Poinsettias are susceptible to certain fungal and bacterial diseases, including leaf spot, stem rot, crown gall, anthracnose, blight, black rot, dieback, grey mold, powdery mildew, rust, scab, mosaic, and root knot nematodes. These tendencies indicate the importance of allowing plants to dry out between waterings and providing good drainage. The University of Vermont Extension provides an excellent way to remember how to care for your poinsettias:

• New Year’s Day - feed with all-purpose houseplant fertilizer
• Valentine’s Day - check for whiteflies; trim back to a height of 5 inches
• St. Patrick’s Day - remove dry and faded leaves; add fresh potting soil
• Memorial Day - cut branches back 2 - 3 inches; repot into a larger container using fresh potting soil
• Father’s Day - move plant outside to a location with indirect light
• Fourth of July - trim again; move into full sunlight; water and feed, as needed
• Labor Day - rinse plant off and move it indoors; reduce feeding as new growth appears
• Autumnal Equinox - put plants in uninterrupted darkness for 13 hours and in bright light for 11 hours each day; nighttime temperatures of 60 degrees F are ideal
• Thanksgiving - reduce water and feeding; place in bright sunny window, rotating for full coverage
• Christmas - enjoy and repeat!

Note: As member of the spurge family, poinsettias do contain latex, which can be an irritant. Contrary to popular belief, however, poinsettias are not poisonous.


Live Christmas trees

Most live Christmas trees sold as miniatures, or tabletop trees, are from the Alberta spruce, Italian stone pine, and Cypress varieties of conifer. Rosemary is also used as a topiary Christmas tree. Conifers prefer cooler temperatures, and more sunlight and moisture, than you will find in most homes, so outdoors is where they would rather be. The same is true for rosemary. Before you decide to put one of these holiday evergreens into the ground, however, be sure to do a little research. Dwarf Alberta spruce will never perform well in high heat, so it will need a protected location. The Colorado blue spruce can reach a height of 75 feet, so you wouldn’t want to plant it under or near a pergola or roof line. Rosemary can take care of itself, once established, providing an excellent border or accent in any Bay Area landscape. If you own your stone pine long enough (20 years or so), you get the added benefit of growing your very own pine nuts!


Amaryllis

Amaryllis (Hippeastrum) plants often arrive looking like a pot of dirt, or a pot of dirt with a stalk sticking out. Fear not! These South American tropical bulbs are very forgiving and long lived and the magnificent blooms are worth the wait. Your Amaryllis will need as much sunlight as you can provide. Temperatures between 68 and 70 degrees F are best. Water sparingly until the stalk appears, and then water more frequently. Just be sure to allow the soil to dry out between waterings. After an amaryllis has bloomed and the flower begins to fade, cut it from the stalk. The stalk will begin to wilt shortly afterward as the bulb pulls nutrients back. The stalk can then be removed completely. Amaryllis plants will then recharge their flowering batteries by producing leaves for the next several months. In early fall, as the leaves begin to turn brown, cut the leaves back to 2 inches from the bulb and remove the bulb from the soil. Clean the bulb and place it in the crisper drawer of your refrigerator for 6 weeks. Just be sure there are no apples nearby, as they will sterilize your amaryllis bulb! After 6 weeks in the cooler, bulbs should be returned to the soil about 8 weeks before blooms are desired. This cycle can continue for several years.


Most holiday plants receive too much water, not enough sunlight, and too much heat to make it through the holiday season. Understanding what these popular holiday gifts need to stay healthy can transform them from short-lived hostess tokens to durable members of the garden, landscape, or home interior.