Helichrysum Silver Mist - Grower Fact

Grower Facts
Helichrysum Silver Mist (Helichrysum microphyllum)

Germination

Silver Mist is offered as a multi-seed pellet (3 seeds per pellet). Do not cover the pellet at sowing. Germination takes 6 to 8 days.

Plug Production

Media

Use a well-drained, disease-free, soilless medium with a pH of 5.5 to 6.3 and a medium initial nutrient charge (EC 0.75 mmhos/cm with a 1:2 extraction).

Temperature

Germination (6 to 8 days): 72 to 76¡ãF (22 to 24¡ãC)
Cotyledon stage: 65 to 72¡ãF (18 to 22¡ãC)
True leaves: 65 to 70¡ãF (18 to 21¡ãC)
Hold plugs: 62 to 65¡ãF (16 to 18¡ãC)

Light

Stage one: Not required.
After germination: 1,000 to 2,500 f.c. (10,000 to 30,000 Lux).
Seedling maturity: Up to 5,000 f.c. (54,000 Lux) if temperature can be controlled.

Humidity

Maintain 95% relative humidity until cotyledons emerge.

Soil Moisture

Keep soil moisture high until radicle emergence, then reduce moisture levels after the radicle penetrates the medium. Do not allow the seedlings to wilt.

Fertilizer

At radicle emergence, apply 50 to 75 ppm N from 15-0-15. As cotyledons expand, increase to 100 to 150 ppm N.

Growth Regulators

Not needed.

Growing On to Finish

Media

Use a well-drained, disease-free, soilless medium with a pH of 5.5 to 6.5 and a medium initial nutrient charge.

Temperature

Nights: 62 to 65¡ãF (16 to 18¡ãC), Days: 65 to 75¡ãF (18 to 24¡ãC)

Light

Keep light levels from moderate to high. Higher light levels result in more silver foliage. Under low light, such as early Spring in the greenhouse, foliage appears more green.

Irrigation

Allow plants to dry slightly between waterings. Avoid watering plants late in the day as constant wet foliage may make the plants susceptible to Botrytis.

Fertilizer

Feed weekly with 200 ppm N in a complete fertilizer. If the plants are underfed, the leaves will become smaller and lower leaves will turn yellow.

Growth Regulators

A tank mix of B-Nine at 2,500 ppm and Bonzi at 30 ppm three weeks after transplant can be used to keep the plants more compact and prevent plants from tangling. This application also makes the foliage more silver.

Pinching

Unlike similar vegetative types, pinching is not needed.

Common Problems

Insects: No serious problems.
Diseases: Botrytis can be a problem if the plants are kept too wet.

Green Thumb Tips

Silver Mist is best used in mixed containers in full sun. Plants prefer drier conditions with good air circulation, so planting in the garden is not recommended in rainy or humid areas.