Gardening is in full swing this summer. If you have any questions, you can use Ask an Expert, an online question-and-answer service from Oregon State University’s Extension Service. OSU Extension faculty and Master Gardeners reply to queries within two business days, usually less. To ask a question, go to the OSU Extension website and type in your question along with your county. Here are some questions asked by other gardeners. What’s yours?.
When I added sulfur to my hydrangeas in the spring, the flowers turned blue or purple. Now they’re just a dull white. What happened?.
A: Hydrangea flowers only retain their color, whether blue, pink, purple, near red, etc. , for a finite amount of time. They then fade to a grayish-white and later on, turn gray or brown. Not unless you have a plant that blooms on new wood, you might not see any more pretty blooms this year.
For the most common French hydrangeas (Hydrangea macrophylla), the flower color indicates the pH of the soil. In strongly acid soil (pH below 6), flowers turn blue. In alkaline soil (pH above 7), flowers turn pink or even red. In slightly acidic or neutral soil (pH 6 to 7), a single shrub may have purple blooms or a mix of blue and pink ones. Keep in mind that selections vary in their sensitivity to pH. White hydrangeas stay white regardless of the soil pH.
Use a soil acidifier to turn your hydrangeas blue. Be sure to follow the directions and use the right amount for your hydrangea’s size. You don’t want to exceed recommendations hoping to get a deep blue hydrangea. Even though this is an organic element, you can easily overdo it.
This is a slow process when it comes to changing the color – don’t expect immediate results. The effects last longer, though, and the soil acidifier will have to be used again next year to keep the blue color. This is not a one-season procedure and your hydrangeas stay blue. Because the hydrangeas bloom for so long in our mild valley, it might need to be done three times a year.
Just so you know, Elizabeth Dean of Wilkerson Mill Gardens has a way to make cut hydrangea flowers last longer in arrangements. Plunge the cut stems in cool water immediately after cutting. Put about an inch of boiling water into a container. Wait a minute or two for it to cool down. Cut the stems to the lengths you want for your arrangement. Hold the bottom 1 inch of the stems in the hot water for about 30 seconds. Then transfer the stems to cool water. Voilà!.
I have a rose bush with very small flowers that look like tea roses but don’t smell very good. It was here when we bought our house five years ago. The bush has been getting leggier each season, even though I have pruned it. The rose buds are only at the top. Is it too late to cut it back really close and still get flowers this year? I cut it back in the winter, but it came back tall and stocky. How can I get this plant to have more fullness at the bottom? – Washington County.
A: If you prune roses once a year and they are still leggy by early summer, it’s probably because they aren’t getting enough sun.
Roses really need full sun. If they don’t get enough sun, they get leggy, bloom less often, and are more likely to get black spot, powdery mildew, and other fungal diseases. If your roses don’t get at least eight hours of full sun a day—ten to twelve hours is better—you should really think about moving them to a sunnier spot this fall or winter, when they are dormant and after you’ve cut them back to a manageable size.
Still, even if roses are getting full sun, there are other things that can cause them to be leggy.
Bottom line is that roses need lots of sun, and no amount of pruning or fertilizer will compensate. – Justin Dune, OSU Extension Master Gardener.
Q: I’ve had this rosemary on the side of my house for a few years in a 20-gallon pot. Its grown but it hasnt exactly thrived. As you can see, its fairly yellowed, and the leaves are a little mottled. I thought it was a white fly issue so I treated for that. The flies appear to be gone but the issue persists. – Multnomah County.
A: Your plant appears to be yellowing, a symptom of a nutrient deficiency, typically nitrogen. Do you fertilize it regularly? Here is an article on their care. Give a balanced (10-10-10) time release fertilizer and it should perk up. – Kris Lamar, OSU Extension.
If you’ve noticed your hydrangeas are starting to fade or turn dull, there could be a few reasons why. Hydrangeas are known for their showy blooms that come in vivid shades of blue, pink, purple and white. But over time, those bright colors can start to dull for a number of reasons.
Soil pH
One of the biggest factors affecting hydrangea color is the pH of the soil. Hydrangeas need more acidic soil to achieve blue blooms usually with a pH below 6.5. For pink or red blooms they need more alkaline soil with a pH above 7.
If your soil pH is off, it affects the availability of aluminum in the soil, which is what turns hydrangea blooms blue. Without enough accessible aluminum, they will start turning more pink or purple instead.
You can test your soil pH with a home testing kit. If it’s not in the ideal range for your desired bloom color you can amend the soil pH with aluminum sulfate to lower it or lime to raise it. But drastic pH changes can stress the plants so make adjustments slowly over time.
Nutrient Deficiencies
Lack of nutrients can also cause faded blooms. Hydrangeas need a balanced diet of primary nutrients like nitrogen, phosphorus and potassium. Too much nitrogen leads to leafy growth instead of flowers. A deficiency in phosphorus impacts blooming, and lack of potassium fades the color.
Have your soil tested to see if any nutrients are lacking. Then you can amend with compost or a balanced organic fertilizer applied in early spring and summer. Avoid high nitrogen fertilizers that promote foliage over blooms.
Sun Exposure
Too much hot sun can take a toll on hydrangeas, causing the blooms to fade or dry out faster. For the best results, situate hydrangeas where they will get morning sun but afternoon shade, especially in hot climates. Dappled shade under trees is ideal.
If relocating isn’t an option, you can improvise with shade structures. Try using shade cloth or installing latticework planted with climbing vines to shelter hydrangeas during peak sun hours. This protects the blooms from harshest rays.
Extreme Temperatures
Just like us, hydrangeas don’t like extreme temperature swings. Frost can damage emerging buds in spring. Very high summer temperatures can cause flowers to brown or shrivel prematurely.
To protect from spring frosts, cover plants with breathable fabric overnight when frost is expected. For summer heat, ensure plants are well watered and situate them out of direct afternoon sun. Providing some shade cover also helps shield from intense sunlight.
Pests and Diseases
A variety of pests like aphids, spider mites and Japanese beetles are attracted to hydrangeas. And fungal diseases like powdery mildew are also common. An infestation or disease outbreak stresses the plants and makes it hard for them to produce vivid blooms.
Check under leaves regularly for signs of pests like sticky honeydew or white dots on foliage. Prune out any diseased stems and fallen leaves to prevent disease spread. Use organic insecticidal soap or neem oil for mild pest infestations. For severe issues, targeted organic pesticides may be needed to get an infestation under control.
Improper Pruning
Pruning hydrangeas at the wrong time removes the next season’s flower buds and limits the plant’s ability to bloom. You should prune immediately after blooming, before the plant sets next year’s buds. For varieties that bloom on old wood, avoid fall or winter pruning when it will remove flower buds.
Age of Plant
As hydrangea shrubs mature over time, their blooms may start to naturally fade a bit even if cared for properly. Very old plants with thick, woody stems tend to have less vibrant blooms compared to younger specimens in their prime.
If your hydrangeas are getting up there in age, you can rejuvenate old plants by pruning selectively to remove old, unproductive stems. This encourages new growth that will flower vigorously. Supplement with compost and organic fertilizer to replenish nutrients.
With some troubleshooting and adjusted care, you can get those beloved hydrangea blooms looking bright and beautiful again. Pay attention to soil pH, nutrients, sunlight, pruning technique and pest control for the best results.
[Know The Reasons With Solutions ] Why Are My Blue Hydrangeas Fading
FAQ
What to do when hydrangeas lose their color?
How do I get the color back in my hydrangeas?
Why is the color fading on my hydrangeas?
Why do hydrangeas lose color?
In conclusion, it is important to understand the factors that can cause a hydrangea to lose its color. Poor soil quality, lack of water, or too much water can all cause the plant to become discolored. Additionally, if the pH of the soil is too alkaline or acidic, this can also lead to discoloration in hydrangeas.
Why are my hydrangea flowers fading?
Finally, soil acidity may be responsible for altering or fading flower color. A popular example of this phenomenon occurs with hydrangeas that seem to be particularly sensitive to the amount of acid in the soil. Paying particular attention to the growing requirements of flowers will help keep their colors from fading.
Why do hydrangea flowers lose luster?
I’ve noticed that these flowers can sometimes lose their luster, with the colors fading or changing completely, and found the reason to be grounded in the very soil they grow from. The pH level of the soil directly impacts the hue of hydrangea flowers.
What if my Hydrangea color is starting to fade?
If your hydrangea’s color is starting to fade, there are several things you can do to help it recover and restore its vibrancy. The first thing you should consider is the soil pH. Hydrangeas tend to prefer slightly acidic soil with a pH between 5.5 and 6.5 for optimal blooming.
Why are my hydrangeas turning purple?
I’ve learned that the primary culprits behind hydrangea color variation are soil pH and the presence of aluminum ions. Blue hydrangeas flourish in acidic soil (pH below 6.5), while pink hydrangeas need alkaline soil (pH above 7). If the soil is somewhere in the middle, one can often see purple or bluish-pink blooms.
Do hydrangea flowers change color?
If your flowers are pink and you were expecting blue you may need to add aluminum sulfate to your soil. If your flowers are blue and you were hoping for pink or red you may need to add garden lime to your soil. Only Hydrangea macrophylla and sometimes Hydrangea serrata have flowers that will change color.