There are a few potential reasons why the colors of your chrysanthemums (also known as mums) may change as they grow and mature. Mums come in a wide variety of colors, but sometimes those colors aren’t stable and can shift or fade as the blooms develop. Let’s explore some of the most common causes behind color changes in mums.
Genetics and Breeding
One major factor is genetics. Most commercially grown mums today are complex hybrids, bred from different parental varieties. This breeding can lead to plants that don’t breed true. What this means is that even though a young mum plant may put out buds of one color, its genetics may cause those blooms to change color as they fully develop.
Some mum varieties are also less genetically stable and prone to more drastic color shifts. As a breeder works with plants over multiple generations, these unstable color attributes can get passed down. So even though you may buy a pot of orange mums from the garden center, some of those blooms may turn yellow or red later on due to the plant’s mix of genetics.
Environmental Factors
The environment that a mum plant is grown in can also influence bloom color. One of the biggest factors is sunlight exposure. Mums grown in high light tend to produce more vibrant, intense colors. Insufficient sunlight can cause those colors to become diluted or fade to lighter shades.
Temperature is another consideration. Cool nighttime temperatures often lead to richer, darker mum colors. Hot temperatures that rise above 80°F can sometimes cause undesirable color changes like fading or muddiness.
Soil pH also plays a role. Mums prefer a slightly acidic soil in the pH range of 6.0-7.0. Letting the soil pH drift too far outside of that range can result in less intense colors.
Finally, the supply of nutrients to the plant affects color. Insufficient nitrogen levels may cause mum blooms to appear more yellow. A phosphorus deficiency can also lead to reduced color intensity.
Plant Age and Health
The overall age and health of a mum plant can impact bloom colors. Young plants tend to produce rich, vibrant colors. But as plants mature and go through several bloom cycles, their colors may naturally fade or change.
Plants under stress from pests, diseases, underwatering, or other factors often experience poorer coloration. Anything that stresses the plant or interferes with its metabolism and pigment production can take away from the brilliance of its bloom colors.
Timing of Bloom Development
When and how quickly a mum’s flowers develop also plays a key role. The pigments responsible for mum colors are produced over time as the blooms form.
Blooms that develop quickly often don’t have enough time to build up strong pigmentation, resulting in diluted or lighter colors. Cool weather that slows down pigment accumulation can have a similar effect.
On the other hand, blooms that develop slowly under warm conditions may have time to gain extra pigment concentrations, leading to richer, darker colors.
Use of Color-Altering Chemicals
In some cases, unexpected color changes may indicate that chemicals were applied to the mum blooms. Growers sometimes use special sprays or dips to alter mum colors artificially. These may enhance colors or convert blooms to entirely new colors.
Common agents used include gibberellic acid, aluminum sulfate, and calcium chloride. These work by influencing pH, interrupting pigment pathways, or selectively destroying certain pigments.
However, the effects of these chemical treatments may not always be stable. As the blooms further mature, their altered colors can shift or fade. So chemical color modification may be responsible if you notice dramatic or unexpected color changes.
Troubleshooting Color Problems
If your mum blooms are displaying undesirable color changes, here are some tips to help get them back on track:
– Move plants to a location with at least 6 hours of direct sun per day to maximize light exposure.
– Avoid overwatering and improve drainage if necessary to prevent root rot.
– Test soil pH and amend as needed to maintain a slightly acidic pH around 6.5.
– Apply a balanced fertilizer to supply nutrients like nitrogen and phosphorus.
– Monitor for pests like aphids or signs of disease and promptly treat any issues.
– Remove any blooms that have already changed color to promote new, healthy growth.
– Stake tall mums to prevent damage from toppling over in wind and rain.
– Cover plants on cold nights if temperatures drop below 50°F.
– Remove flowers as they fade to encourage a continuous supply of new blooms.
Enjoying and Using Changed Blooms
Even though altered mum colors may not be what you originally anticipated, there are still ways to enjoy the blooms:
– Use them in floral arrangements and bouquets, mixed with other fall flowers.
– Cut changed blooms to display in a vase indoors. They will last 1-2 weeks.
– Leave the blooms on the plant for seasonal interest in beds and borders.
– Make mini bouquets from cut stems and give as fall gifts.
– Float individual blooms in bowls of water to use as table centerpieces.
– Dry the blooms upside down to preserve as everlastings for crafts.
– Use changed blooms as garden mulch by mowing them with a lawn mower after they fade.
Choosing Stable Varieties for Reliable Color
If you want mums with reliably stable colors that don’t change unexpectedly, choose these varieties:
| Variety | Color |
|---|---|
| Cherry Bomb | Red |
| Sea Shell | White |
| Golden Glow | Yellow |
| Radiant Purple | Purple |
These varieties have been specially bred to bloom true to color with minimal shifting. Sticking with proven stable cultivars is the best way to prevent unexpected color changes.
Using Color Shifts to Your Advantage
While frustrating, the color instability of some mums can also provide creative opportunities:
– Plant a mix of different colored mums together for a mutating, kaleidoscope effect.
– Use blooms that change from yellow to red to evoke the turning of fall leaves.
– Highlight the color changes in arrangements and photographs.
– Have kids monitor the blooms for surprises and document color shifts over time.
– Use changing blooms to teach principles of genetics and plant breeding.
– Appreciate the beauty and unpredictability of nature’s infinite variety.
So if your mum’s colors aren’t what you expected, try to embrace the change! With some patience and creativity, you can find ways to appreciate the blooms.
Conclusion
While changing colors in mums may be frustrating, it is usually due to genetics, environment, plant health, bloom timing, or use of altering chemicals. Troubleshoot issues, choose stable varieties, and find creative ways to use the changing blooms. With some flexibility, you can enjoy the diverse range of colors produced by these popular fall flowers. Expect the unexpected and you’ll find there is beauty in both the consistency and inconstancy of nature.