© 2020 Syngenta. All rights reserved. The publication and its content is proprietary to Syngenta. It may not be

photocopied or reproduced in any form. Product names marked ® or ™, Syngenta Flowers, the SYNGENTA

Wordmark and the SYNGENTA Logo are trademarks of a Syngenta Group Company. Syngenta has exercised

reasonable care and skill in compiling this publication. All data in this brochure is intended for general guidance only

and the user should apply it only for the purposes for which it has been created and in accordance with his own

knowledge and experience of local conditions. Syngenta cannot accept any liability in connection with this advice.

Classification: PUBLICTM

CROP MANUAL

Helianthus annuus

“SUNBLAST”

Central Europe

North Europe

From cuttings to finished

| Crop Manual | 2Classification: PUBLICTM

Finished Plant “Sunblast”

Helianthus annuus

Remarks

Vegetative interspecific Helianthus is a facultative short-day plant.

Young plants are delivered under SHORT DAY propagation

Estimated finished crop time from transplant of a 4 week old 72 X-tray plug and finished at an average daily temperature (ADT) of 20⁰C under short days.

Plants flower under both short days and long days, but flowering is 1 to 2 weeks faster under short days.

Required-pinch at the 6th or 7th leaf node to promote branching.

Crop time is approx. 5-10 days faster at an ADT 23⁰C versus 20⁰C

Series Type Leaf color Pot size Comment

Sunfinity from seed Vigorous dark green 17 - 23 cm focus on 17-19 cm

Calendar Week 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38

Scheduling transplant potting from

72 X-Tray with pinching to a Ø 21 cm

pot.

Pinch in finished crop after approx

one week.

Pinch will delay crop by 7 - 10 days

P & S F F

P & S F F

P & S F F

P & S F F

P & S F F

P & S F F

P & S F F

P & S F F

P & S F F

P & S F F

P & S F F

| Crop Manual | 3Classification: PUBLICTM

Fertilization & Substrate

Important to keep EC levels of

the growing media in the range

of 1,3 – 1,7. Measure the EC

every week. Sunblast is a high

energy plant and needs a lot of

feeding increase the EC in the

substrate is at desired level.

Spacing

Spacing on time during the

culture period is crucial to avoid

stretched and uncontrollable

growth. Recommend spacing

directly after pinch and cotyledon

shoot removal at 5 - 6 pl/m²

Tips & Tricks

Required to improve branching

and control vigor.

Pinch after 6–7 nodes developed

on the stem leaving 4 nodes

only.

The nodes of Sunblast are

scattered so a pinch to 6/7 nodes

would leave 8 leaves.

This is a hard pinch. Do not pinch

too early to avoid issues with

uneven branching.

Irrigation

Sunblast needs to be irrigated on

a regular basis. The Ec given by

feeding is relatively

high because it is a vigorous

plant and consumes a lot.

If the pots are becoming too dry

root damage can happen

because of salt accumulation.

Plug

Plugs are delivered under

SHORT DAY propagation.

Important to transplant the plant

in the center of the pot!

It's very important to apply several PGR application during finishing. Avoid applying PGRs too heavily to try to control Sunblast. Sunblast has a growth spurt and applying PGR at the right moments is very effective.

Recommended application:Sprench (heavy spray). Preferred application: Alar 4gr / 1 ltr1.Laterals breaking /showing after the pinch. 2.Visible bud. This stage is very important.3. At showing color.Higher rates may be necessary under high light and temperature conditions (SET).Spray is also possible but needs to be done more frequently to keep control over the plant.

PGR alternatives: Regalis: 1,5 gr/ltrBonzi: 3ml – 5ml/ltr (After pinch at least once a week to avoid stretching)

Negative results with Cycocel: leaf damages

Cultivation Advice

Helianthus annuus

Pests

Preventive insecticide: Against

chewing insects (caterpillar) Aphid,

spider mites, trips, whitefly.

Diseases

Other soil borne diseases like

Phytopthora Botrytis, Pythium,

Rhizoctonia, Thielaviopsis, Downy

Mildew, rust.

| Crop Manual | 4Classification: PUBLICTM

Legend

Recommendations

Helianthus annuus

Culture guideline at optimum average daily temperature 20–22oC:

Culture week 1 2 3 4 5 6 7 8 9 10 11 12 13

Handling TP & S F F

PGR PD PD

Tempature D/N 18–20°C

Light10-11 hr short days length for optimum flowering results.

Shading ☀short day <12 h/short day treatment

Humidity 50%

Moisture Alternate 4–2

pH 5,8–6,0

EC growing medium 1,75–2,0 mS/cm > 2,25 mS/cm

EC feeding in mS/cm 2,0–2,5 mS/cm 2,5–3,0 mS/cm

Fertilizer N : K 1 : 2

| Crop Manual | 5Classification: PUBLICTM

Height 6 / 7 nodes

Young plant ready to pinch

Production Guideline Pot Size

19 cm

Country

Germany

Pinch 5 nodes

Young plant pinched back to 4

nodes, 8 leaves

Pinch 5 nodes Very strong rootsystem

Side shoots removed to create a

uniform plant together with pinch

Helianthus annuus

1 2

Young shoots are showing

aftre a couple of days

3 4