Q. Can I start feeding my fruit trees now or should I wait until spring? A. It is best to wait a couple of weeks, toward the end of January, before new growth sets in and up through about March for a single application.             A convenient method of application are fertilizer spikes which can be pounded into wet soil about a foot from the tree using the plastic cap that is usually sold with them. You pay for that convenience and lower mess. Fertilizer spikes have the added advantage of releasing nutrients slower than a handful of fertilizer.               You can use GOOD compost if you want but good compost contains about 1 to 2% nitrogen compared to traditional fertilizers which can be 20% or more. So you have to use much more compost compared to a fertilizer.             Don’t forget your single iron application also in January. Use the EDDHA form of iron chelate and follow label directions. It contains about 6% iron but is not an organic source.              For organic gardeners blood meal can be used as a nitrogen source as well as iron but has about a 30:1 ratio of iron compared to EDDHA so you need to use a lot more compared to the chelate. Blood meal has about 0.2% iron in it.             You can mix the blood meal with the compost if you like. Compost, although not labeled as a fertilizer, is a complete source of plant nutrients. Adding blood meal to it enhances the uptake of iron and compost helps to lower soil pH also helping to make the iron more available to the plant.             Alternatively you can make one application in January or half in January and half after you harvest.              If citrus or other winter tender fruit trees nothing after June to keep succulent growth at a minimum before winter.