Grower Facts

Dusty Miller Maritima
(Senecio cineraria)

Germination
- Time of radicle emergence (3-6 days)
- Soil temperature 72-75°F (22-24°C).
- Keep media evenly moist, but not saturated.
- Do not cover or bury the seed.
- Light is not necessary for germination until radicle emergence.
- Soil pH 5.5-5.8 and soluble salts (EC) less than 0.75 mmhos/cm (2:1 extraction).
- Dusty Miller is very sensitive to high salts, particularly high ammonium, during germination.
- Keep ammonium levels less than 10 ppm.

Plug Production
STAGE 1 Time of radicle emergence (3-6 days)
- Soil temperature 72-75°F (22-24°C).
- Keep media evenly moist, but not saturated.
- Do not cover or bury the seed.
- Light is not necessary for germination until radicle emergence.
- Soil pH 5.5-5.8 and soluble salts (EC) less than 0.75 mmhos/cm (2:1 extraction).
- Dusty Miller is very sensitive to high salts, particularly high ammonium, during germination.
- Keep ammonium levels less than 10 ppm.

STAGE 2 Stem and cotyledon emergence (7-14 days)
- Soil temperature 70-75°F (21-24°C).
- Reduce moisture levels once radicle emergence occurs! Allow the soil to dry out slightly before watering for best germination and rooting.
- Keep soil pH 5.5-5.8 and EC less than 0.75? mmhos/cm.
- Keep ammonium levels less than 10 ppm.
- Begin fertilizing with 50 75 ppm N from 14 0 14 or a calcium/potassium nitrate feed once cotyledons are fully expanded.
- Alternate feed with clear water.
- Irrigate early in the day so foliage is dry by nightfall to prevent diseases.

STAGE 3 Growth and development of true leaves (14-21 days)
- Soil temperature 65-70°F (18-21°C).
- Allow the soil to dry thoroughly between irrigations but avoid permanent wilting to promote root growth and control shoot growth.
- Maintain soil pH 5.5-5.8 and EC less than 1.0 mmhos/cm.
- Increase feed to 100 150 ppm N from 20 10 20 alternating with 14 0 14 or other calcium/ potassium nitrate fertilizer.
- Fertilize every 2 3 irrigations.
- If using 15-0-15 supplement with magnesium 1 2x during this stage, using magnesium sulfate (16 oz/100 gal) or magnesium nitrate. Do not mix magnesium sulfate with calcium nitrate as precipitate will form!
- Use DIF whenever possible, especially the first 2 hours after sunrise, to control plant height.
- B-Nine and Bonzi can be used to control height.

STAGE 4 Plants ready for transplanting or shipping (7 days)
- Soil temperature 60-62°F (16-17°C).
- Allow soil to dry thoroughly between irrigations.
- Maintain soil pH 5.5-5.8 and EC less than 0.75 mmhos/cm.
- Fertilize with 14 0 14 or calcium/potassium nitrate feed at 100 150 ppm N as needed.
- Keep foliage as dry as possible to reduce disease.

Growing On to Finish
TEMPERATURE
Night: 60-65°F (16-18°C)
Day: 55-60°F (13-16°C)
Reduce temperature to 45-55°F (7-13°C) for toning and holding.

LIGHT
Maintain light levels as high as possible while maintaining moderate temperatures.

MEDIA
Use a well-drained, disease-free soil-less medium with a medium initial nutrient charge and a pH 5.5-6.0.

FERTILIZATION
Fertilize every other irrigation with 15-0-15 alternating with 20-10-20 at 150-200 ppm nitrogen. Maintain medium electrical conductivity around 1.0 mmhos/cm (using 1:2 extraction).

CONTROLLING HEIGHT
Once plants are rooted to the sides of the containers they can be allowed to wilt prior to irrigation to provide some height control. Height can also be controlled by withholding fertilizer, especially phosphorous and ammonium-form nitrogen. Dusty Miller are responsive to day/night temperature differential (DIF), and are shorter with a negative DIF. B-Nine and Bonzi can be used to control height.

Post Production Care
TEMPERATURE
Night: 60-65F (16-18C)
Day: 55-60F (13-16C)
Optimum conditions may be difficult to maintain, especially if plants are displayed outside. Using a negative DIF will help keep the plants short and of high quality.

LIGHT:
Dusty Miller prefer full sun to partial shade.

COMMON PROBLEMS:
Insects: Aphid, Spider mites
Diseases: Alternaria