Geranium Cultivation Techniques and Care Management Methods
Varieties: Marerick, Orbit, Multibloom, Elite, OrangeApeal series
Germination period
----Preparation stage
All geranium varieties can be grown under the same conditions. (Germination)
pH: 6.2-6.5 A pH below 6.0 can lead to tipburn and the inability to absorb sodium, iron and magnesium (13-2-13-6Ca-3Mg)
Stage 1
The radicle appears within 1-2 days.
Appearance characteristics: At the end of Stage 1, roots are 0.64-1.27 cm long, and true leaves appear.
Moisture: A saturated substrate is important for geraniums to absorb water. Cover the seeds with a layer of vermiculite to maintain moisture; the substrate surface should be kept moist at all times.
Substrate temperature: 23°C. Above 25°C can affect normal germination; below 22°C will reduce the germination rate and affect germination uniformity.
Substrate EC: 0.75-1.0. A high EC value will inhibit rooting.
Light: Light has no major effect on germination.
Stage 2
When roots are 0.64-1.27 cm long, geraniums need a large amount of oxygen. Keeping the substrate [well aerated] can increase oxygen availability and promote the rooting process.
Appearance characteristics: At the end of Stage 2, roots are 1.27-2.54 cm long, and the first true leaf begins to grow. If there are few fibrous roots, reduce water and lower the temperature to 18°C. Increase the calcium content.
Moisture: Let the substrate dry out a little, so its color changes from black to light brown.
Substrate temperature: 21°-24°C
Fertilizer: Alternately apply 50-75 ppm calcium fertilizer (13-2-13-6Ca-3Mg) and potassium nitrate (15-5-15). Phosphorus fertilizer should not exceed 5-7 ppm. Geraniums are sensitive to ammonia; ammonia fertilizer should not exceed 10 ppm, otherwise it will cause leaf growth.
EC value: 1.0-1.5
Light: To advance the flowering period, provide 16-8 hours of supplemental light at 3500-4500 lux. This is not necessary for the Multibloom series.
----Stage 3
Note: Attention to seedling bud growth; high ammonia fertilizer and humidity can cause leggy growth.
Appearance characteristics: At the end of Stage 3, roots are 3.81-5.08 cm long, seedlings are 2.54 cm tall, and 2 true leaves have appeared.
Water: Let the substrate dry and re-wet once a day to enhance oxygen uptake. Saturation for more than 36 hours can reduce seedling vigor; seedlings should not be allowed to dry out excessively.
Substrate temperature: 65°-70°F (18°C-21°C).
Fertilizer: See Stage 2. If leggy growth occurs, stop applying ammonia fertilizer and reduce the frequency of fertilizer application.
EC value: 1.5-2.0
Light: Increase light to 4500-6000 lux, but not exceeding 35,000 lux.
Stage 4
Coordinated plant growth is controlled by light, temperature and watering.
Appearance characteristics: At the end of Stage 4, the root system can firmly support the plant.
Water: See Stage 3
Substrate temperature: 62°F-65°F (16°C-18°C).
Fertilizer: See Stage 3. If the plants are weak and spindly, apply additional calcium fertilizer to coordinate seedling growth.
Substrate EC: See Stage 3
Light: If natural light is weak, supplemental light can be provided.
Air: Under high light conditions, 1000 ppm carbon dioxide can be applied to advance the flowering period.
Growth regulation: After 3-5 true leaves appear, apply 750 ppm Cyco-ce1.
Growth period
Note: The Multibloom series is grown differently from other geraniums.
After 6-7 weeks Multibloom reveals flower buds. Therefore, rapid growth of Multibloom must be maintained; water and fertilizer supply should not be over-controlled, otherwise Multibloom will be no different from other series.
Substrate: Choose a substrate with good aeration, 10-20% permeability.
Substrate pH: 6.0-6.5. A pH below 5.5 can lead to sodium, iron and manganese toxicity; the characteristic of low pH is yellow leaves.
Water: For the Multibloom series, let the substrate dry slightly between waterings; for other series, keep it slightly moist between waterings. Excessive drying will increase the salt concentration around the roots, thereby continuously damaging root hairs. Excessive drying: the characteristic is that bottom leaves change from red to yellow, and root tips necrose.
Fertilizer: Apply 200 ppm nitrogen fertilizer.
EC value: 1.5-2.0
Temperature: 60°-65°F (16-18°C) at night, 70°-75°F (21°C-24°C) during the day. After flower buds appear, controlling the night temperature can regulate flowering time.
Supplemental light: Provide light 2-3 weeks after transplanting, for 14-18 hours; a light level of 300-500 footcandles (3000-5000 lux) can advance the flowering period. Geraniums are sensitive to light; the more light, the earlier they flower and the faster they grow.
Growth regulation: After 3-5 true leaves appear, applying 750 ppm cycocel 4-5 times can control growth. Note: After flower buds appear, do not apply cycocel; applying cycocel later can lead to excessive flower formation or poor shape.
Common pests: Thrips