How do I control my slab EC?

In the Season Dynamics we state that it is important to have a target EC for each of the different periods during the crop.

To control the EC to the target levels it is important to use the proper measuring strategy so that you can make small and frequent changes to your irrigation strategy. It is always easier and safer to make frequent small changes than to make big changes when the EC has got too high.

The important factors for good EC control are:

• good initial root distribution after planting (first 6 to 8 weeks);
• the correct dose size per dripper;
• correct use of the Daily Dynamics.

Period 1 in the Daily Dynamics is very important to re-fill the slabs as evenly as possible with the correct dose size. This will not only give better EC control later in the day but also reduce the variation in EC around the glasshouse.

To reduce EC it is necessary to flush the slab more. This can be done by:

• increasing the frequency (by light or time);
• increasing the dose size (within the recommended range).

So look for a higher percentage of drain especially in period 2 and period 3 of the Daily Dynamics.

Take care if reducing the drip EC that the Delta EC does not get too big (>3).