Hydrangea Tips

Hydrangea Tips

How do I change the color of my hydrangea flower?

The color of the hydrangeas will vary considerably due to the type of soil that they are growing in. The blues are best in acid soil. The amount of aluminum available in the soil and the ability of a particular variety to absorb it will control the degree of blueness. The reds and pinks enjoy an alkaline or neutral soil. The whites will stay white but usually enjoy the same conditions as the reds or pinks.

You’ll need to raise the acidity of the soil to encourage “blueing” of the flowers. This can be done by soaking the soil around the plant several times at weekly intervals in the spring and again in the fall with aluminum sulfate. The aluminum sulfate should be applied at the rate of 1/4 ounce per gallon of water.

Apply time to high acid soil to encourage pink to red blooms. The lim should be applied at a rate of one pound to every ten square feet of surface area once or twice a year until the desired color is obtained.

Please note: color correction takes some weeks or even months to occur. Rain, irrigation, and soil composition also affect the acidity of your soil.

Hardly any blooms this Spring?

A blooming problem is likely pruning, although too much sun can contribute to the problem. Most hydrangeas bloom on old wood, and if you prune too harshly there are no buds for the next blooming season. We recommend trimming just 10-20% of the plant, or just above a “node”. We trim our garden in the fall as we’ve found the more harshly and later we prune, the less blooms we have the following summer.

Sun can slowly hurt the blooming ability of a hydrangea. Too much direct sunlight drains the plant of moisture. If the foliage is still green and healthy, the hydrangea is most likely using all the water to retain its health and the bloom is left with nothing. The best environment for most hydrangeas is morning sun and afternoon shade. Unseasonably low temperatures after a mild winter also cause a lack of blooming on hydrangeas.

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