Frequently Asked Questions

Question:
Are there any trees or shrubs that bloom in winter?
Answer:

While most trees and shrubs bloom in spring or summer, witch hazels are a notable exception. Common witch hazel (Hamamelis virginiana) blooms from mid-October to early December.  Vernal witch hazel (Hamamelis vernalis) and...

Question:
What types of Christmas trees are available?
Answer:

Tree species commonly available at tree farms and commercial lots in Iowa include Scotch pine, white pine, red pine, Fraser fir, balsam fir, Canaan fir, Douglas fir, white spruce, and Colorado spruce.  
 

Question:
How can I propagate an African violet?
Answer:

African violets are easily propagated by leaf cuttings.  Select a firm, healthy leaf and cut it off with a sharp knife.  Leave 1 to 1½ inches of the leaf stem (petiole) attached to the leaf blade.  Fill a pot with a moistened 50:50...

Question:
How can I propagate a Christmas cactus?
Answer:

Christmas cacti are easy to propagate.  Remove sections of the plant consisting of 2 to 5 flattened stem segments.  Cut or pinch off each section at a joint.  Allow the cut/pinched ends of the cuttings to callus overnight. ...

Question:
How do I care for a poinsettia?
Answer:

Place the poinsettia in a plant sleeve or carefully wrap it before transporting the plant home.  Exposing the poinsettia to freezing temperatures, even for a few minutes, may cause its bracts and leaves to blacken and drop.  As soon as...

Question:
Is the poinsettia poisonous?
Answer:

The poinsettia has long been regarded as poisonous.  However, research conducted at various institutions has shown the poinsettia is not poisonous.  While the poinsettia is not poisonous, it is not intended for human or animal...

Question:
How can I propagate a rubber tree?
Answer:

The common rubber tree (Ficus elastica) can be propagated by air layering.  Air layering is a procedure used to induce roots to form on a plant stem while it is still attached to the parent plant.  Complete or partial girdling...

Question:
I have a beautiful rex begonia. Would it be helpful to mist the plant during the winter months?
Answer:

While rex begonias and many other houseplants prefer high relative humidities, misting is ineffective unless you’re prepared to mist the plants several times a day.  Also, rex begonias are not fond of water on their foliage. 

The...

Question:
How do you force paperwhite narcissus?
Answer:

Paperwhite narcissus are easy to force indoors.   The bulbs can be forced in clear, shallow bowls (no drainage holes) or pots. 

When forcing paperwhite narcissus in bowls, partially fill the container with washed gravel or...

Question:
What factors should be considered when purchasing a Christmas tree for the holidays?
Answer:

A few decisions should be made before going out to buy a Christmas tree. Decide where you are going to place the tree in the home. Be sure to choose a location away from heat sources, such as a fireplace or radiator. Also, decide on the size (...

Question:
How can I determine the freshness of a cut Christmas tree?
Answer:

The freshness of cut Christmas trees can be determined with a few simple tests. Gently run your hand over a branch. The needles on a fresh tree will be pliable. Those on a dry tree will be brittle. Another test is to lift the tree by the trunk...

Question:
What is the best way to store a cut Christmas tree?
Answer:

If you don’t intend to set up the Christmas tree immediately, place the tree in a cool, sheltered location. An unheated garage or shed is often a suitable storage site. (The sun and wind dries out trees stored outdoors.) Put the butt of the tree...

Question:
Should I add any material to the water to prolong the freshness of my Christmas tree?
Answer:

Do not add molasses, sugar, soft drinks, aspirin, or commercial products to the water. Additives provide no real benefit. The keys to keeping a Christmas tree fresh are to place the tree away from any heat source (fireplace, heater, radiator, etc...

Question:
How long can a cut Christmas tree remain in the house?
Answer:

The length of time a cut Christmas tree can remain in the home is determined by the tree species, the freshness of the tree at purchase, and its placement and care in the home. In general, a fresh, well-cared-for Christmas tree should be able to...

Question:
Is snow beneficial to landscape plants?
Answer:

A layer of snow is beneficial to many plants in the garden and landscape.  A layer of snow protects plants from extreme cold and the drying effects from sun and wind.  A layer of snow also prevents repeated freezing and thawing of the...

Question:
My shrubs are flopping over due to the weight of heavy, wet snow. What should I do?
Answer:

The weight of heavy, wet snow can cause considerable damage to small trees and shrubs.  When heavy, wet snow accumulates on small trees and shrubs, gently shake the snow from their branches or carefully brush off the snow with a broom....

Question:
My poinsettia suddenly wilted and died. Why?
Answer:

The sudden death of the poinsettia was likely due to a root rot.  Pythium and Rhizoctonia root rots typically occur when plants are watered too frequently and the potting soil is kept saturated.  Allow the surface of the potting soil to...

Question:
Small, white insects flutter about my poinsettia when I water the plant. What are they and how do I control them?
Answer:

The small, white insects are likely whiteflies.  Whiteflies are common insect pests of poinsettia, hibiscus, chrysanthemum, and a number of other indoor plants.  They are most often noticed when watering or handling a plant.  When...

Question:
Can paperwhite narcissus bulbs be saved after they have been forced indoors?
Answer:

Paperwhite narcissus bulbs should be discarded after flowering.  Paperwhites cannot be successfully forced again and are not winter hardy outdoors. 

Question:
When are trees and shrubs most vulnerable to rabbit browsing?
Answer:

In the home landscape, rabbits feed on herbaceous plants (annuals, perennials, vegetables, and grasses) during the growing season.  Trees and shrubs become food sources in late fall and winter (December through March).  Damage to trees...

Question:
My sweet potatoes have become dry and stringy. What caused this?
Answer:

It’s likely the sweet potatoes were not cured and stored properly.  After harvest, sweet potatoes should be cured for 7 to 10 days at a temperature of 80 to 85 degrees Fahrenheit and relative humidity of 80 to 90 percent.  (These...

Question:
An amaryllis bulb saved from a previous year produces leaves, but doesn’t bloom. Why?
Answer:

An amaryllis bulb purchased at a garden center or other retail business typically blooms 6 to 8 weeks after the bulb is potted up.  In succeeding years, proper cultural practices must be followed to get the bulb to bloom on an annual basis...