1) what are the NPK numbers of the strawberry fertilizer and how much do you mix per water? Are you also adding calcium nitrate separately to tyhe nutes, if so, at what rate.
2) are they getting enough light?
3) What is the name of the variety?
4) Do the roots and crown look healthy?

It may actually be overfertilization or underfertilization = opposites. You say it is a special strawberry fertilizer. Please don't tell me you bought that dubious premixed all in one from Amazon's marketplace - third party.

If you are giving them enough light and the fertilizer is not excessive, but lacking in the micros, you may save only save them with a foliar splashing of a manganese sulfate very dilute solution. These are two opposite strategies but if you answer the four questions we probably can say. Strawberries are a sensitive crop when it comes to properly applying nitrogen just right which makes them more challenging than the other greens.

There are many poor nutrient combinations that can cause your picture, so unless someone else out there recognizes it without doubt, best to cover all the bases on the growing conditions. The small fruits sort of point to N-dificiency (and Mn deficiency) but let's see where you have/had the NPK is to try & figure out what happened.

This post was edited by PupillaCharites on Tue, Sep 3, 13 at 15:50

Defiantly the fertilizer just by looking at it. First the older foliage is burnt on edges, typical over fert. Then energy is diverted away from the buds because of nutrient lockout and at the same time the new growth is nutrient lockout yellow and stunted. Change out your water. Whats the guaranteed analysis of your fert. And what ppm are you using.