7.3. Changes of the nutrient solution during different phenological growing stages (De Kreij et al., 1997 simplified)
Stage	Adaptation, mmol/l
	NH4	K	Ca	Mg	NO3	SO4	H3PO4	Ba	Fea
Start	−1b	−3.5	−1.25	+1c	−1.5	+1	−0.5	+10	+10
Flower first truss		−1.2	+0.3	+0.3
Flower third truss		+1.0	−0.25	−0.25
Flower fifth truss		+3.5	−1.25	−0.5
Flower tenth truss		+1.0	−0.25	−0.25

^*EC, electrical conductivity.

^ain μmol/l;

^b“−” reduce;

^c“+” increase compared with the standard (see Table 7.2).