For example, if the soil is acidic (pH below 7), then it can make the blue and purple pigments in the flowers more intense. This works best with hydrangeas, delphiniums, and certain varieties of roses.
On the other hand, if the soil is alkaline (pH above 7), then it can make pink, orange, and red pigments in the flowers more vivid. This works the best with pink hydrangeas and roses.
2. Experiment with Fertilizers
Phosphorus (P) is the key element behind coloration in flowers, so it would be a good idea to look for a blend that has a higher number of it, like 10-30-10 and 15-30-15.
Do make sure that you are following the label for dosage and application.
3. Use Temperature Stress
When the plants are stressed, they respond differently to it, and this may, sometimes, can alter flower coloration in certain species. For example:
- Exposing poinsettias to cooler temperatures (around 60-65°F or 15-18°C) can enhance the coloration their red bracts.
- A temperature range of 50-60°F (10-15°C), can encourage more intense and vibrant colors in snapdragon blooms.
- A mild temperature stress of around 50-60°F (10-15°C) will make sweet alyssum more vivid.
- Primroses get more saturated in the temperature range of 50-60°F (10-15°C).
4. Experiment with Water Stress