| By |
| B. Rosie Lerner |
| |
| Purdue Extension |
| Consumer |
| Horticulturist |
|
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10-16-03
Evergreen Needles Don't Last Forever
Evergreens provide green color all year long, but that doesn't mean the
individual needles live forever. Evergreens do shed their older needles
to make room for new growth. But what makes them evergreen is that they
retain some foliage all year long, instead of shedding all of the leaves
at once.
Evergreen needles have varying life spans, depending on the species.
Arborvitae and pine needles live for 2 years, while spruce needles live
3-10 years. Some species of evergreens have a more noticeable leaf drop
than others. In autumn, arborvitae and white pine will drop their 2-year
old needles all at once, which can be quite alarming, if you don't realize
that it's perfectly normal.
On other species, needle drop occurs gradually, with a small number of
needles falling at one time. The older needles of yew shrubs will turn
yellow and drop in late spring or early summer. Broad-leaved evergreens,
such as rhododendrons, drop their 2-3 year-old leaves in late summer and
early fall.
Inner and lower needles that are hidden from light are usually the first
to drop. Pruning excess growth and dead limbs can help open the plant
to more light. But, for most plants, there's no need to worry; they are
just doing what comes naturally.
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