The magical, changeable nature of hydrangeas

Eye-catching, exquisite, and delicate, yet robust, are some of the descriptive words that come to mind whenever I see a flowering hydrangea shrub. These beauties are easy to spot in many Fallbrook landscapes.

One of the first things I came to admire about these plants, as a child, were the intriguing hues of their flowers – the luscious blues, ethereal purples, soft creams, and powerful pinks these plants are known for. They have always struck me as startlingly beautiful. The profuse blooms on the mature hydrangeas in the Fallbrook neighborhood I grew up in never went unnoticed in my day-to-day travels.

Although I know a few stories of trials and tribulations relating to growing hydrangeas, the bottom line is that if they are planted in the recommended fashion, they are easy to grow and provide their brilliant blooms from mid-summer through fall. The blooms have a pretty decent retention time, which is a benefit.

Historically, hydrangeas are said to have been first introduced in 1739 by Sir Joseph Banks.

The most popular variety is the Bigleaf Hydrangea, due to its large, mesmerizing blooms.

Experts say hydrangeas can be planted at any time during the year, however it is best to purchase a plant while it is blooming. This allows the buyer to see the exact color of the blooms they will enjoy. It is also optimum to plant hydrangeas in the spring (after frost), early summer, or fall. Avoid planting hydrangeas during the hottest heat of the summer, otherwise it will require quite frequent watering.

I can attest to the fact that hydrangeas prefer locations with only partial (or filtered) sun. The most prosperous plants I have seen are tucked partially under the eave of a house or in a sheltered patio area. It is also true that they do best if planted facing east. In Fallbrook, that provides the protection they thrive in. They prefer morning sun and afternoon shade is what it comes down to. It is also important to plant them in soil that drains well.

One very intriguing thing about hydrangeas is that it's possible to manipulate their color. To me, that is a fascinating experiment with nature.

Generally speaking, experts will say that to manipulate the bloom colors, one must simply adjust the soil pH factor. However, there are a few more details necessary than that to achieve the goal.

First, don't spend energy on the variety with white or cream-colored flowers – the only change that will occur with these is that at times, their blooms will take on a faint pink tinge at the end of the season, but that's about it.

The plants featuring the pink, blue, and purple blooms, can be manipulated easier. Their shades do respond to changes in the chemistry of the soil.

According to experts, when grown in alkaline soil, the blooms become pinker; when grown in acidic soil, the bloom colors run bluer.

According to Grangetto's Farm & Garden Supply, "Because it’s the soil chemistry that determines the bloom color, the variety names given to these types of hydrangeas means very little when it comes to bloom color. For instance, Nikko Blue, Pretty in Pink, Forever Pink and Blue Deckle, all have an almost equal chance of blooming pink or blue, depending on the soil they are planted in.

So remember, if purchasing a hydrangea in bloom, one cannot be sure the plant will produce the same color flowers once it’s planted in particular garden soil."

"To manipulate the color of a hydrangea’s blooms, you need

to manipulate your soil’s pH level and mineral content," Grangetto's experts said. "This is not something you do just once. In order to maintain growing conditions that result in a specific bloom color, you may need to apply special soil amendments several times during the growing season."

"To really experiment with the color of a hydrangea’s blooms, consider growing the plant in a large pot. Because you will be working with a much smaller amount of soil, it will be much easier to maintain the desired pH of the soil."

To begin, one should test the pH of their soil for its levels. Soil pH test kits are easily available at Grangetto's.

"Be mindful that the health of the plant should be your first priority," Grangetto's said. "It’s quite difficult to make a dramatic change in soil pH, and doing so can adversely affect the overall health of the plant."

What a hydrangea is fed also affects their flowering. "To keep the color of pink and blue blooms, treatments to the soil need to be started in fall and early winter ahead of the blooming period," Grangetto's noted. "Alkaline or neutral soils make pink flowers, while acid soils yield blue flowers. Southern California tends to have alkaline soil, so if you don’t treat the soil, you will end up with pink flowers."

Remember, white/cream flowers will remain the same. Some pinks will stay pink, and other pinks will only change to purple instead of blue.

"To create blue flowers, you need to alter the soil so that it is acidic – a pH of 4.5 to 5.0," said Grangetto's. "To do so, use a balanced, water soluble, acidic fertilizer with little or no phosphates, since phosphates are alkaline."

"Each fall or winter, also apply one tablespoon of aluminum sulfate per foot of plant height. Mix with water and drench the soil.

To maintain pink flowers, you will need a soil with a pH of 7.0 to 7.5. Use a balanced, water soluble fertilizer and add superphosphates to the soil in the fall or winter."

To learn more about planting and caring for hydrangeas, visit

the Fallbrook Grangetto's Farm & Garden Supply store at 530 E. Alvarado Street, phone (760) 728-6127, or access www.grangettos.com.

Information source: Grangettos Farm & Garden Supply