Why Your Evergreens Lose Needles in the Fall

 

Fall.  The time of year where we enjoy autumns radiant reds, brilliant oranges, luminous yellows and the yellowing of evergreen needles?    Well, yes.  But this shouldn’t cause a panic or create any fear that you may lose your evergreen, it is simply the natural progression of plants.

White Pine fall needle drop

White Pine fall needle drop

 

Like deciduous trees, conifers (a tree that bears cones and is typically evergreen) will lose at least some of their inner needles every year.  These needles that are dropped from the inner part of the plant is a normal part of the plants life cycle.  Different species will shed at different stages, and while some species may take 5 or more years before they drop their old needles, other species only take one.

White Pine fall needle drop.

White Pine fall needle drop.

 

Two of these that drop yearly are Eastern White Pine (Pinus strobus) and Arborvitae (Thuja) making for a dramatic, if not somewhat frightening, departure of foliage.  In many cases the inner foliage will turn yellow first and then change to a deep, straw colored hue and finally turn brown and drop.  This is perfectly normal and new growth will appear the following spring.
Emerald Arborvitae fall needle drop.

Emerald Arborvitae fall needle drop.

 

However, if there are browning tips or overall yellowing you may want to have your conifer inspected for pests or disease.  The browning tips could also be a result of drought or winter desiccation which is caused by low soil moisture, freezing temperatures and wind burn.
Bald Cypress is a deciduous conifer

Bald Cypress is a deciduous conifer

There are some conifers that will drop all of their foliage every fall.  These are called deciduous conifers.  Bald Cypress (Taxodium distichum) and Weeping Larch (Larix decidua ‘Pendula’) are two relatively common deciduous conifers in the St. Louis area.

Bald Cypress (a deciduous conifer) drops all of its foliage in the fall.

Bald Cypress (a deciduous conifer) drops all of its foliage in the fall.

 

Other evergreens that lose their old foliage but are not conifers are Rhododendron, Holly (Ilex) and Southern Magnolia (Magnolia grandiflora).  While all evergreens drop their old foliage, these 3 broadleaf evergreens tend to worry people the most when it occurs.
Rhododendron will lose its large leaves every 1 to 2 years in the fall while Holly will lose every year.  Holly, however, will drop their old foliage in the spring as the new growth appears.  Another broadleaf evergreen that drops its foliage primarily in the spring is the Southern Magnolia.
Southern Magnolias drop their old foliage in the spring.

Southern Magnolias drop their old foliage in the spring.

 

 Southern Magnolia tend to be especially worrisome to people when they drop their foliage.  One reason is because they tend to be fairly expensive, another is because they are often placed in very prominent locations in the landscape and when they drop their large leaves it can be rather panic inducing.  It also doesn’t help that it drops the bulk of its leaves at a time of year when everything else in nature is beginning to shine.  Spring.
Bracken Brown Southern Magnolia

Bracken Brown Southern Magnolia

The biggest thing with Southern Magnolia, as with all the other evergreens and conifers that drop their foliage, is the new growth that comes after.  As long as your conifers and other evergreens have new growth the following spring and your Southern Magnolia pushes new growth in the summer, then all is well in your garden and landscape!