Culture Information

Callie^®
Calibrachoa

Calibrachoa hybrida

Product form: Vegetative

Containers: Pints, Quarts, Gallons, Hanging Baskets

Habit: Trailing/Spreading

Garden Specifications

Garden height: 4–8" (10–20 cm) tall

Garden width: 14–18" (35–45 cm) wide

Exposure: Full Sun

USDA zone: 10–11

AHS zone: 11–2

Product use: Containers, Hanging Baskets, Patio Pots, Combos

Propagation of Unrooted Cuttings

Root emergence: 10–12 days

Rooting hormone: Recommended. A 0.1% (1,000 ppm) IBA concentration using either powder or liquid formulations can be applied to the lower portion of the cutting stem. Be careful not to coat the leaves or entire cutting–excess application can cause burning and damage to the cutting. Another option is to apply an overhead heavy spray to the cuttings (penetrating the rooting media) using water-soluble K-IBA at 250–300 ppm 24–48 hours after sticking. Do not use overhead applications of alcohol-based IBA solutions (ex. Dip 'n Grow^®).

Bottom heat temperature: 72–74 °F (22–23 °C) for the first three weeks. After roots are well developed, temperatures can be lowered to hold and tone the cuttings.

Misting: Mist schedules vary depending on light and temperature conditions. Apply just enough moisture to rehydrate the cuttings and keep them from wilting. Cuttings should be hydrated and in a non-wilted stage within 24 hours after sticking. Cuttings that continue to wilt heavily after 24 hours will callus unevenly and will be delayed in rooting. CapSil^® (spray adjuvant) can be sprayed on the cuttings at a rate of 2–4 oz/100 gal within 1–2 days after sticking to help in rehydration of the cuttings. Misting should be significantly reduced after 2–3 days and after cuttings become fully hydrated. Calibrachoas are particularly sensitive to overmisting. They will show chlorosis and have poor rooting when too much mist is applied, particularly early on after sticking the cuttings.

Recommended tray size: 105-cell (30 mm) or larger

Propagation timing: 4.5–5 weeks for a 105-cell tray; add more rooting time for significantly larger cell sizes.

Temperature

Day: 72–74 °F (22–23 °C)

Night: 72–74 °F (22–23 °C)

Lighting

Day extension lighting: Not necessary

Light intensity: 200–250 µmol·m⁻²·s⁻¹ for the first two weeks after sticking or until root development occurs. Light levels can be increased up to 600 µmol·m⁻²·s⁻¹ as rooting increases and the cutting matures.

Day length response: Facultative long day

Daily light integral (DLI): 4–6 mol·m⁻²·d⁻¹ for the first two weeks after sticking or until root development occurs. DLI can be increased to greater than 12 mol·m⁻²·d⁻¹ after root formation.

Media pH: 5.6–6.0

Media EC: SME EC: 0.9–1.3 mS/cm, Press/Squeeze Method EC: 1.4–2.0 mS/cm

Fertilizer: Begin fertilization at 100 ppm nitrogen when roots become visible. Rates can be increased up to 200 ppm nitrogen after roots become well developed. Use primarily Cal-Mag^® (calcium nitrate + magnesium nitrate) fertilizers in propagation to prevent unwanted stretch. Supplemental feeding with additional iron (i.e., iron chelate) will help prevent iron deficiency and leaf tip chlorosis.

Pinching: Recommended

Plant growth regulators (PGRs): Callie^® calibrachoas have a range of vigor, with some being relatively compact to others having more of a medium to medium-vigorous habit. To keep plants under control, a spray of B-Nine^® WSG at 1,500–2,500 ppm can be applied after cuttings are well-rooted and vegetative growth begins. Tank mix Florel^® at 350–500 ppm with the B-Nine^® WSG solution listed above to increase growth control and to improve branching. These Florel^® + B-Nine^® WSG combo sprays should be applied to actively growing plants and done ideally before pinching. Do not spray B-Nine^® WSG or Florel^® + B-Nine^® WSG tank mixes on stressed or weak cuttings. For all sprays listed above, the mist should be off for a minimum of one hour for the PGR to be absorbed into the leaf tissue.

Finishing

Temperature

Day: 70–72 °F (21–22 °C)

Night: 62–64 °F (17–18 °C)

Average daily temperature: 66–68 °F (19–20 °C)

Lighting

Day extension lighting: Beneficial to 14 hours

Light intensity: 800–1,200 µmol·m⁻²·s⁻¹

Day length response: Facultative long day

Daily light integral (DLI): 16–18 mol·m⁻²·d⁻¹

Transplanting: Transplant directly into the finished container. Place the rooting media slightly below the level of media in the container. Make sure the root ball is covered and the liner is situated in the center of the pot.

Media pH: 5.5–5.9

Media EC: SME EC: 1.5–2.1 mS/cm, PourThru EC: 2.3–3.2 mS/cm

Fertilizer: 200–250 ppm N

Pinching: Yes, one pinch is recommended 7–10 days after transplant. A second pinch can be given to plants grown in large baskets and containers. This second pinch can occur shortly before a final Bonzi^® drench. Use proper sanitation when pinching or shearing calibrachoa. Calibrachoa and other solanaceous crops are highly susceptible to tobacco mosaic virus (TMV), which can be easily transmitted by mechanical means.

Plant growth regulators (PGRs): Callie^® calibrachoas have a range of vigor, with some being relatively compact to others having more of a medium to medium-vigorous habit. To keep plants under control, sprays of either B-Nine^® WSG (2,500–3,500 ppm) or Sumagic^® (10–20 ppm) can be applied to the plants as needed. A spray of Florel^® (350–500 ppm) or Florel^® (350–500 ppm) + B-Nine^® WSG (2,500 ppm) can also applied early on to control growth and improve branching. For the best-looking plants, a Bonzi^® drench (2–3 ppm) should be applied to the media about four weeks before full finish and sale.

Tech tip: Keep the pH down in the mid-5.0s to avoid tip yellowing—drench with iron chelate if necessary. Avoid overwatering of young plants. Plants can be pinched twice in baskets and larger containers (once in prop, once after transplant). An early Florel^® or Florel^® + B-Nine^® WSG spray improves branching. Mid-crop Bonzi^® drenches are the key to beautiful mounded baskets. Watch for aphids. High DLIs and moderate-to-cool finishing temperatures produce high-quality calibrachoa. Use proper sanitation when pinching or shearing calibrachoa to prevent possible virus spread.

Moisture level: Media should be allowed to dry between irrigations. Alternate between moisture level 2 and 4. 2 - MEDIUM: Soil is light brown in color, no water can be extracted from soil, and soil will crumble apart. 4 - WET: Soil is dark brown but not shiny, no free water is seen at the surface of the soil, when pressed or squeezed water drips easily, and trays are heavy with a visible bend in the middle.

Common pests: Aphids, thrips, budworms

Common diseases: Botrytis, powdery mildew, viruses (TMV, TSWV)

Scheduling

Estimated finish crop time is from transplant of a 105-cell tray and finished at the recommended average daily temperature of 68 °F (20 °C).

Example crop schedule for a 2.5 quart