The following Q&A is from Iowa State University Extension’s garden experts:
I recently purchased a Norfolk Island pine. How do I care for it?
The Norfolk Island pine is a popular houseplant. During the holiday season, many individuals turn their plants into living Christmas trees by decorating them with miniature lights, ribbons and ornaments. The Norfolk Island pine thrives indoors when given good, consistent care. Place the Norfolk Island pine in a brightly lit location near an east, west or south window. Rotate the plant weekly to prevent the plant from growing toward the light and becoming lopsided.
Thoroughly water the Norfolk Island pine when the soil surface becomes dry to the touch. Discard the excess water, which drains out the bottom of the pot. From spring to early fall, fertilize the plant with a dilute fertilizer solution every 2 to 4 weeks. A temperature of 55 to 70 degrees F is suitable for the Norfolk Island pine. Winter is often a difficult time because of low relative humidity levels in most homes. Raise the humidity level around the Norfolk Island pine with a humidifier or place the plant on a pebble tray. Low relative humidity levels, insufficient light, or infrequent watering may induce browning of branch tips and lead to the loss of the lower branches.
Which trees and shrubs provide food for birds during the winter months?
When attempting to attract birds to the landscape, trees and shrubs that provide food during the winter months are extremely important as natural foods are most limited at this time of year. Trees that provide food for birds in winter include hackberry (Celtis occidentalis), hawthorn (Crataegus species), eastern red cedar (Juniperus virginiana) and crabapple (Malus species). Shrubs that provide food for birds include red chokeberry (Aronia arbutifolia), northern bayberry (Myrica pensylvanica), sumac (Rhus species), roses (native species and Rosa rugosa), snowberry (Symphoricarpos species), nannyberry (Viburnum lentago) and American cranberrybush viburnum (Viburnum trilobum).
Can I dispose of my wood ashes in the garden?
Wood ashes contain small amounts of several plant nutrients. The nutrient content of wood ashes depends on the type of wood burned, the thoroughness of its burning, and other factors. Generally, wood ashes contain 5 to 7 percent potash, 1 percent phosphate, and small amounts of other elements. However, the largest component of wood ashes is calcium carbonate. Calcium carbonate is a liming material. Liming materials raise the soil pH.
The soil pH is important because it affects the availability of essential nutrients. The pH scale runs from 0 to 14. Any pH below 7.0 is acidic and any pH above 7.0 is alkaline. A pH of 7.0 is neutral. Most vegetables and perennials grow best in slightly acidic soils with a pH between 6.0 and 7.0. Plants may not perform as well in soils with a pH above 7.0 because of the reduced availability of some essential nutrients.
Avoid applying wood ashes to garden areas with a pH above 7.0. Applying wood ashes to alkaline soils may raise the soil pH and reduce the availability of some plant nutrients. An application of 10 to 20 pounds of wood ashes per 1,000 square feet should be safe if the soil pH is below 7.0. If the soil pH in your garden is unknown, conduct a soil test to determine the pH of your soil before applying wood ashes to flower or vegetable gardens.