Tips For Growing Hydrangeas

If you've read this blog for any length of time, you probably know that my favorite flower is the Hydrangea.  We have three hydrangea bushes in our backyard.

 Most recently, I added these to my landscaping.

My mother in law knows that I love hydrangeas and sends me information on them.  I thought I would share some of this knowledge with you.

Where should I plant my Hydrangea?

Hydrangeas grow best in moist, well-drained soil.  Hydrangeas are happiest with a combination of sun and shade.  In the South, the best place to plant your hydrangea is in a location where sunlight is filtered.  It is best if they get morning sun and afternoon shade.  In the north, hydrangeas are able to stand more sun.  They can deal with full sun, so long as they get plenty of water and aren't planted where they are hit with winter winds.  You also want to be careful which variety of hydrangea you purchase.  If you live in a climate where early Spring frost is an issue, you may want to go with a hardier hydrangea...

perhaps the smooth hydrangea

or the peegee hydrangea.  These varieties are also drought tolerant.

The most popular species is Hydrangea macrophylla, which is commonly known as bigleaf, French, garden or florist’s hydrangea. 

Why doesn't my hydrangea bloom?


There are three main reasons your hydrangeas are not blooming.  First, too much shade.  If you have a hydrangea that used to bloom, consider what has happened to your landscaping around it.  Have bushes and trees grown around it limiting it's sunlight?  If so, you may want to consider moving it.  Second, improper pruning.  Bigleaf and oakleaf hydrangeas flower on previous year’s growth, so potential flowers buds would be removed if the plants were pruned in fall, winter or spring. Panicle and smooth hydrangea flower on this year’s growth, so pruning them in early summer would reduce or eliminate flowering for that year.  I found that out last year when I pruned my hydrangea in early summer and all but ended my flowers for the season.  The third reason applies mainly to bigleaf hydrangea.  The most common reason for lack of flowering in bigleaf hydrangea is unfavorable weather.  Bigleaf hydrangeas respond quickly to warm temperatures in late winter and early spring by breaking dormancy and producing new leaves.  However, often these warm temperatures are followed by periods of frost and freezing temperatures.  Depending on the damage caused by the weather can greatly effect the amount of flowers for the season.

Is there anything I can do to make my bigleaf hydrangea flower more reliably?


It may be possible to protect plants from weather-related flower bud damage by covering them during late spring freezes with a blanket.  




How do I change the color of my hydrangea?


Flower color is dependent on aluminum availability. Aluminum is necessary to produce the blue pigment for which bigleaf hydrangea is known for. Most garden soils have adequate aluminum, but the aluminum will not be available to the plant if the soil pH is high. For most bigleaf hydrangea, blue flowers will be produced in acidic soil (pH 5.5 and lower), whereas neutral to alkaline soils (pH 6.5 and higher) will usually produce pink flowers. Between pH 5.5 and pH 6.5, the flowers will be purple or a mixture of blue and pink flowers will be found on the same plant.

To change the color of a hydrangea planted in the garden, it is necessary to change the soil pH. To raise the pH, add lime. One way of lowering the pH of the soil is to add aluminum sulfate. Additions of acidic organic matter (peat, pine bark) can also help lower soil pH. Exact amounts of lime or aluminum sulfate necessary to get the desired flower color will vary depending on current soil pH and soil type.  


Hope these tips help you achieve beautiful hydrangea flowers all summer long.

Don't forget to stop back tonight for my Swing into Spring party.  The link will open up tonight at 8pm EST.  Hope to see you then.


-Judy