I don't believe that the jobe fertilizer spikes supply all the nutrients the plants will need. I bought some on clearance before I learned about gritty mix and nutritional requirements, and haven't found a use for them now that I'm using the 111 mix.

I also didn't easily find any fertilizers or micronutrient mixes that would sufficiently complement the spikes, but once I read about FP I went for that, so I didn't look very hard.

I'm not sure how easy they would be to apply to your trees, but people have mentioned some controlled release fertilizers in a positive light. I thought those were best mixed in with the medium when potting the plant, but I may be mistaken.

It might be possible to use the spikes as a stop gap measure, even if they can't support your trees long term. Hopefully other folks will have better advice though (I'm sure they will).

I think I'd opt for one of the controlled release fertilizers with micro-nutrients in as close to a 3:1:2 ratio as possible before I'd use the spikes. I think Osmocote makes a 19-6-12 with the minors, and Dynamite makes an All-Purpose 18-6-8, and their 13-5-11 Palm & Citrus Fertilizer should be great, too.

Al

Thanks - I'll try the Osmscote.

I have been reading about the new miracle gro crf shake n feed for tomatoes, fruits, and vegetables 9-4-12 which claims to have calcium and other need micros. Seems like a good alternative.

Jay,
that formulation doesn't make sense from the plant's perspective,
particularly for heavy feeders like tomatoes (and other fruits/vegetables).

Plants use more nitrogen than either phosphorous or potassium, and they use these nutrients
in a 3:1:2 ratio. In addition, supplying excess phosphorous or potassium won't force
plants to bloom - it'll simply increase the level of dissolved solids in the soil mix,
it will waste product flushing out of the soil, and it will waste the grower's time.
For those who wish to manipulate their plants in such a way, it would be better to simply
limit the nitrogen while continuing to supply the appropriate ratio of P and K.

The numbers you mention would be very good if only they were reversed, 12-4-9.

Josh