My plants have been re-potted in organic soil but are not growing – these are not flowering plants. I have Jobes Spike’s for flowering plants, can I still use them for these non flowering ones?
The packaging on your fertilizer spikes will likely show three numbers such as 8-9-12. The first number, (N) nitrogen, promotes healthy green growth. The second number, (P) phosphorous, promotes root growth, flowering and fruiting. The third number, (K) potassium, is for overall plant health.
As your fertilizer spikes have been produced for feeding flowering plants, the second and third numbers are higher.
Ideally, plant food specifically designed for feeding indoor plants, which are grown for foliage, should have a higher first number – that is, more (N) nitrogen. A balanced plant food with equal amounts of (N) nitrogen, (P) phosphorous and (K) potassium, would also be a good choice.
It won’t hurt your plants to use the fertilizer spikes you have, but when you next purchase a plant food for your indoor foliage plants, consider a balanced plant food such as 20-20-20 (used at half strength), or one with a higher first number.
Also, please be aware that many houseplants slow down their growth during the winter months, so feeding at this time should be kept to a minimum.
This link provides some good information on fertilizing houseplants.