The ways to maximize the yield of gerberas grown in greenhouse

| English

The nutrition recommendations, using Haifa's fertilizers, also help to fight magnesium and iron deficiencies in gerbera

Growing conditions: Greenhouse
Plant density: Plants/Ha

Nutrition Recommendations
Fertigation:
Soil type: Clay

Growth stage	Nutrients Demand (kg/day/ha)			Fertilizers recommendations (kg/ha/day)
Growth stage	N	P₂O₅	K₂O	Multi-K	MAP	AS
Establishment	1.5	0.75	1.5	3.2	1.2	5.4
Vegetative development	3	1	3	6.4	1.6	9.5
Flower initiation - cutting	3	1	4.5	9.5	1.6	8.75

Soil type: sandy
Proportional application (ppm in irrigation water)*

Growth stage	Nutrients Demand (g/m3)			Fertilizers recommendations (g/m3)
Growth stage	N	P₂O₅	K₂O	Multi-K	MAP	AS
Establishment	80	40	80	170	60	350
Vegetative development	150	65	150	330	110	660
Flower initiation - cutting	200	90	200	430	150	880

Multi-K = Potassium nitrate (13% Nitrogen, 46% K₂O)
Haifa MAP = Mono-ammonium Phosphate (12% Nitrogen, 61% P₂O₅ )
AS = Ammonium sulfate (21-0-0)

* Based on irrigation rate of 20-30 m3/ha/day

Nutrition database for gerberas

Parameter	Concentration
	Rockwool		Rockwool (reuse drainage)				Plant – dry matter (13-15%)
	Nutrient Solution	Root Environ.			Nutrient Solution	Root Environ.	Guiding Range	Deficient	Excessive
EC (mS/cm)	1.7	2.2			1.1	2.2
	(mg/l)			(mg/l)			(%)
NH₄	27.0	< 9.0			13.5	< 9.0
N- NH₄	21.0	< 6.9			10.4	< 6.9
K-sap							0.59–0.74
K	215.1	234.6			176.0	234.6	3.91–5.00	< 1.96
Ca	120.3	200.5			64.2	200.5	1.00–2.41
Mg	24.3	48.6			9.7	48.6	0.24–0.63
N, total							2.52–4.90
NO₃	697.5	806.0			449.5	806.0
N- NO₃	157.4	181.9			101.5	181.9
S, total
SO₄	120.1	240.3			67.3	240.3
P								0.25-0.62
H₂PO₄	121.3	97.0			58.2	97.0
							mg/Kg (ppm)
Fe	1.955	2.234			1.396	2.234	55.9-111.7		> 558.5**
Mn	0.275	0.165			0.275	0.165	38.5-48.3		> 219.7*
Zn	0.262	0.327			0.196	0.327	32.7-52.3
B	0.324	0.432			0.216	0.432	30.2-40.0
Cu	0.048	0.064			0.032	0.064	3.8-12.7
Mo	0.048	-			0.048	-

* Dependent on the cultivar
** In petals
Important note: The a/m database was prepared to fit Dutch conditions (low transpiration and low EC of the water). Considerable and proportional reduction in the concentration of the macronutrients should be required to offset for lower quality water prevailing in other conditions.

sources:

N. Straver. Nutrient solutions for vegetables and flowers grown in water or substrates. 10th Ed. 1994.
C. de Kreij, Sonneveld C., Warmenhoven M.G. and Straver N.A. Guide values for nutrient element contents of vegetables and flowers under glass. 3rd Ed. 1992.

Combating Mn & Fe deficiencies in Gerbera

Source: FlowerTech 1999, vol. 2/ no. 2, p.30.

A deficiency of nutrients such as manganese and iron can affect the size and other floral characteristic of the Gerbera.
Manganese deficiency leads to the younger leaves displaying interveinel chlorosis with small chlorotic patches.
With a severe deficiency, the patches spread and coalesce, resulting in chlorotic mottling. Subsequently the foliage turns yellow leaving the veins green.

Iron deficiency initially appears as chlorosis at the basal portion of the leaves and spreads towards the anterior leaf margin, showing yellow-green chlorotic mottling. The chlorotic areas turn brown and show necrosis.
To correct these deficiencies, a combined foliar spray of manganese sulphate and ferrous sulphate each at 200 mg/litre of water twice at an interval of 15 days over the foliage, during April-May will help to increase the size and number of flowers.

The ways to maximize the yield of gerberas grown in greenhouse

The nutrition recommendations, using Haifa's fertilizers, also help to fight magnesium and iron deficiencies in gerbera

Nutrition database for gerberas

sources:

Combating Mn & Fe deficiencies in Gerbera

You may also be interested in:

Multi-K potassium nitrate products

Haifa Micro™ - Water soluble chelated micronutrients