Fertilising your strawberry crop

Page last updated: Monday, 15 December 2014 - 1:19pm

Please note: This content may be out of date and is currently under review.

Balanced plant nutrition is essential to achieving high yields of quality strawberries. To work well it must be combined with efficient irrigation because nutrients are transported into and around the strawberry plant by water.

Extensive fertiliser and irrigation trials carried out in the Wanneroo area on a leading grower's property from 2005 to 2007 showed that with good fertiliser and irrigation practices, each plant can consistently produce up to 1.5 kilograms of well flavoured marketable fruit each season. This web page summarises the results from that work.

Research at Wanneroo showed that with good management, commercial scale plantings of strawberries yielded 1.2 to 1.5 kilograms of marketable fruit per plant over three consecutive growing seasons (Camarosa and Camino Real varieties). This was achieved by fertigating one to four times a day with a nutrient solution applying 2kg of nitrogen per hectare per day in fixed ratio with other nutrients. This equates to about 450kg of nitrogen and 6.2 megalitres (ML) of water per hectare over a season (April to November).

Nutrient solution

In two of the three years, 2006 and 2007, the same nutrient solution was applied daily throughout the life of the crop from planting to the end of harvest. All fertilisers were applied by fertigation through the drip irrigation system. No changes to ingredient components or nutrient ratios were made in these two years and there were no pre-plant fertiliser applications.

Plants were fertigated at each watering with a stock nutrient solution supplied from two 1000 litre tanks. The concentrations of nutrients supplied from these two tanks were:

  • Calcium nitrate............................................. 50.0g/L
  • Magnesium sulphate..................................... 24.9g/L
  • Mono-ammonium phosphate (MAP) ............. 12.7g/L
  • Potassium nitrate.......................................... 50.0g/L

All of the calcium nitrate and half of the potassium nitrate were dissolved in Tank A and the other fertilisers were dissolved in Tank B. Each tank had its own injection pump and the injection rate of stock solution from each tank during the fertigation cycle was 1 litre per minute. The resulting quantities of fertiliser applied per hectare of crop using this method are shown in Table 1.

Table 1 Composition of nutrient solution applied each day






Applied nutrients


N P K Ca Mg

Calcium nitrate
(15.5% N, 19% Ca)

6.5 1


Potassium nitrate
(13% N, 38% K)
6.4 0.8


Magnesium sulphate
(9.9% Mg)

Mono-ammonium phosphate
(11% N, 22.8% P)
1.9 0.2 0.4

Total nutrient applied


0.4 2.4 1.2 0.3

This fertiliser program applies about 450kg of nitrogen, 100kg of phosphorus, 580kg of potassium, 288kg of calcium and 76kg of magnesium per hectare per season (April to November).

Trace elements

You can either add all the trace elements at the start of the season as a broadcast application which is then rotary hoed into the soil, or you can add them to the nutrient solution mixture listed above (see table below for rates).

If the trace elements are added in the sulphate form rather than the chelate form, then you need to add them to Tank A.

Fertiliser Formula



Iron chelate Fe-EDTA 13% 860
Manganese sulphate MnSO4.H20 169
Borax Na2B4O7.10H2O 953
Zinc sulphate ZnSO4.7H2O 201
Copper sulphate CuSO4.5H2O 19
Sodium molybdate Na2MoO4.2H2O 12

Important points

  • The electrical conductivity (EC) of the nutrient solution emitted from your drippers should not exceed 2EC units (2μS/cm). High salt concentration can damage the crop. Refer to note below on calibrating nutrient solution injection pumps.
  • This nutrient solution is best applied using a two-tank fertigation system.
  • Calcium should not be mixed in the same tank as fertilisers containing phosphorus.
  • When fertigating, keep the soil at or near field capacity to avoid concentrating salts in the root zone. As the soil dries, the concentration of salts increases.

Calibrating nutrient solution injection pumps

  • Start irrigation and injection pumps.
  • Adjust each injection pump to the same output.
  • Measure the EC at the dripper and adjust each injection pump up or down to get an EC of about 2.2mS (for example, 1.7mS for fertiliser and 0.5mS for bore water).


Contact information

Rohan Prince
+61 (0)8 9368 3210


Aileen Reid