Hi growers in Cascadia,

For those fruit growers in our area west of the Cascade Range (which I realize includes a lot of microclimates), I'm wondering when you first begin fertilizing your bush-fruits and fruit trees.  With the amount of wintertime rainfall that we get which can leach some nutrients from the soil, it can be difficult to decide when is the best time to begin fertilizing, whether at half- or full-strength.  

Some buds are beginning to swell (such as Japanese plums, pears, and blueberries), but one doesn't want to fertilize and promote vigorous growth (--largely with nitrogen--) which might be damaged in a late freeze during late February or March (--or April if the weather really wigs-out).

On the other hand, with many nutrients leached from the soil by autumn and winter rains, fruiting plants may need a little extra nutrition to assist them in their early, post-dormancy growth.  Woody fruiting plants that are deficient in nutrients may be attacked by insects (such as shot-hole beetles, Scolytus rugulosus), which will attack plants that are under stress or duress.  

So far (at least locally), I consider the winter to have been relatively mild in terms of cold.  Each day I assess which plants on the property (native and non-native) are beginning to grow in order to try and estimate "the right time" to begin fertilizing fruit trees, blueberries, black currants, etc.  When it comes to fertilizing, I've completely gotten away from N-P-K fertilizers, try to amend our difficult clay soil appropriately, and then use a kelp and fish emulsion mix.  My problem is always when to begin the fertilizing process each year given the vagaries of our climate.

Those of you who garden successfully here west of the Cascade Range:  Are there particular signs that you look for as a proper time to begin fertilizing plants for the year's new season of growth?  Input would be greatly appreciated!

Reinettes