When & How to Fertilizer Your Fruit Trees

Fruit trees need good nutrition to grow and produce an abundant harvest, just like vegetables, flowers, and other plants. In our helpful video, Tricia explains if, when, and how much to fertilize your fruit trees. Or keep reading here to learn the 5 Easy Steps for fertilizing your fruit trees!

Step One: Know When to Fertilize

  • There IS a right and wrong time to fertilize your trees.
  • Just before bud break is the perfect time. This is when your trees are beginning their annual growth cycle and “eat” the most food.
  • You can fertilize up to a month before this, or if you’ve miss the ideal moment and the trees have already begun to bloom, you can still fertilize until June.
  • Do NOT fertilize in late summer or fall, though, because the new growth put on by the tree can be damaged by frost. If you’ve waited too late in the year and still want to feed your trees, you can mulch them with compost and top-dress with soft rock phosphate; however you should avoid all nitrogen fertilizers.

Step Two: Measure to Decide if You Need to Fertilize

Not all fruit trees need fertilizer every year and they don’t need it in the same amounts. This can change from year to year depending on a variety of factors, so be sure to measure annually.

What will happen if the incorrect amount of fertilizer is given?

  • Too much fertilizer will lead to lots of leaves and shoots, and not a lot of fruit. It could even make your trees weak from too-rapid growth, risking broken branches later in its life.
  • Too little fertilizer can cause slow growth and under-performance, so you don’t get as much fruit as you want at harvest time. Not fertilizing fruit trees grown in poor soil can even lead to nutrient deficiencies, poor health, and trees that are less able to fight off diseases and pests.

Luckily, fruit trees are pretty good at telling you what they need. All you need is a tape measure and a few minutes of your time. Be sure to take your measurements in the winter or early spring while it is dormant, before the tree starts growing again for the new season.

Measure Annual Growth

Steps in Measuring the Previous Year's Growth

  • First–locate last year’s growth rings. The growth ring is the point on the branch where the tree started growing in the previous season. The newest growth that you will be measuring is often a different color than the rest of the branch.
  • Second–measure from the growth ring all the way out to the end of the branch. Repeat these measurements at several spots around the tree.
  • Third–calculate the average of these measurements. This is the previous season’s “annual growth” of the tree.

Repeat this step for each of your trees. Even if you have several trees of the same variety and age, they may not have grown at the same rate and thus have different fertilizer needs. Note–if you have pruned your tree significantly more than normal, so that you’ve removed over 20% of its canopy within the last year, don’t fertilize until the next year.

Check the Chart to Evaluate Growth

Finally, use this chart to evaluate your tree’s annual growth. If the tree’s growth rate is at the low end of, or below, annual target growth, then you should fertilize the tree this year. If your tree’s growth rate is at the high end of, or above, the annual target growth rate, you do not need to fertilize this year (but measure again next year in case that changes!).

Annual Growth Rates
  • Peaches and nectarines–non-bearing young trees should grow 18"-24", mature bearing trees should grow 12"-18".
  • Apples and pears–non-bearing young trees should grow 18"-30", mature bearing pears and non-spur type apples should grow 12"-18".
  • Bearing spur apples should grow 6"-10".
  • Plums and sweet cherries–non-bearing young trees should grow 22"-36", mature bearing trees should grow 8".
  • Tart cherries–non-bearing young trees should grow 12"-24", bearing mature trees should grow 8".

Step Three: Choose the Right Fertilizer

  • Fruit trees prefer an organic, high nitrogen fertilizer.
  • Blood meal, soybean meal, composted chicken manure, cottonseed meal, and feather meal are all good, organic nitrogen sources.
  • There are also specially formulated fruit tree fertilizers.
  • In addition to nitrogen, your tree needs other macro and micronutrients too. Adding compost when you fertilize is a good way to provide organic matter and trace minerals. Azomite or Cascade Remineralizing Soil Boost are good sources of trace minerals.

A soil test can tell you whether you need to add more phosphorus, potassium and other nutrients.

Step Four: Calculate how Much Fertilizer to Use

More is not always better when it comes to fertilizing your fruit trees. Now that you know that your tree needs fertilizer, and have picked the perfect fertilizer to use, you’ll need to determine the correct amount to use on each tree.

For those of us who did not excel in math—fear not—we will walk you through the fertilizer calculations.

The amount of fertilizer you will use is calculated based on the age or size of the tree, and the nitrogen-value on the package.

Determining How Much Fertilizer to Use

  • Trees need 0.10 pounds of “actual nitrogen” per year of age, or per inch of trunk diameter (measured 1 foot above the ground). The maximum you should give a fruit tree in a year is 1 pound of actual nitrogen.
  • For example, if your tree has a diameter of 5 inches (or, if your tree is 5 years old), multiply 5 by 0.10 pounds of nitrogen, equals 0.5 lb. This means that the tree will need 0.5 lb of actual nitrogen.
  • But wait, you’re not done yet! “Actual nitrogen” pounds is not the as simple as just weighing out that amount of fertilizer, because there is more in a fertilizer than just nitrogen.
  • The NPK numbers on fertilizer show the percentage of nutrients per pound of fertilizer, not the actual amount. N, P and K refer to nitrogen, phosphorus, and potassium.
  • For example, if the N listed on the fertilizer package is 7 (meaning 7% nitrogen), such as with E.B. Stone’s Fruit Tree fertilizer, then there is 0.07 pounds of actual nitrogen for every pound of fertilizer.
  • To calculate how much fertilizer to apply, divide the amount of actual nitrogen the tree needs by the amount of actual nitrogen per pound in the fertilizer.
  • So, using the previous examples, a five-year-old apple tree needs 0.5 lb of nitrogen. The E.B. Stone Fruit Tree Fertilizer has an N-value of 7 on the package, meaning it has 0.07 lb nitrogen per pound of fertilizer. Half a pound, or 0.5 lb, divided by 0.07 lb equals 7 lbs. The answer–7 pounds–is the amount of this fertilizer to apply to the tree.

Step Five: Applying the Fertilizer

To help the tree “eat” the fertilizer most efficiently, apply the fertilizer evenly starting a foot away from the trunk and continue all the way to the “drip line.” The drip line is the perimeter of the tree’s furthest reaching branches.

  • The easiest way to do this is simply by spreading the fertilizer on the ground and raking it in.
  • Digging a series of small holes is another method of applying fertilizer. It is a bit more work, but it best ensures the fertilizer is getting to the tree roots, especially when using a fertilizer containing less-soluble nutrients like phosphorus and mycorrhizae.
  • Dig the holes six inches down and 12” to 18” apart, throughout the same area as you would have spread the fertilizer. To make the digging job easy you can use an auger attachment with a cordless drill. Sprinkle a little bit of fertilizer in each hole until it is used up.
  • Once you have finished fertilizing, spread an inch-deep layer of compost around the tree and water well.

Resources

For more information on all aspects of fruit trees—selecting and planting a bare root, pruning, controlling pests, and even how to preserve your harvest—browse our videos and articles in Fruit Tree Central. Some staff-favorite books on fruit trees are The Home Orchard from UC Davis, along with The Fruit Grower's Bible.

Keep on living the dream with your organic orchard, now that you know when and how to fertilize your fruit trees.

51 comments

  • This year, I had a bumper crop of apples on my 10 year old Liberty apple tree. While I have had some apples in the past, I’ve never had anywhere near this many and I’ve always had to harvest early to try to beat the squirrels. This year…the squirrels have left my apples alone. I am not complaining but I am interested in why. I seem to recall, years ago, reading something in a book or on the internet that indicated that young fruit trees naturally produce some chemical to attract squirrels and other pests to “thin” fruit for them to allow the tree to produce stronger roots. Then, when the tree is mature, it produces another chemical to repulse pests like squirrels. I can’t locate where I read this so I don’t know if I am remembering correctly or making it up or possibly reinterpreting portions of Peter Wohlleben’s book “The Hidden Life of Trees”. FWIW, we had a mild winter this year and abundant rain this spring and summer. I’ve also noticed that the pignut hickories nearby have almost no nuts on them and wondered if maybe the squirrels headed elsewhere in the neighborhood to find nuts. But I do see squirrels in my apple tree occasionally and they are definitely not eating the apples. Any ideas why?

    Mellie
  • Ankur, you can fertilize with a fertilizer that has more phosphorus in it. Right now, in August, you do not want to give them any supplemental nitrogen. It is too late in the season. You also want to make sure that in the early summer, like June, you want to thin your fruit so you will not get alternate bearing (every other year).

    Suzanne
  • I have a peach tree . I leve in Chicago. There were no peaches observed this year but had some last year and abundant a year before that. So what could be the problem if I had to start getting peaches from same tree again

    Ankur Desai
  • Hi Lucia. I too was having problems with fruit trees here in North San Diego County ( Warner Springs), until I realized we live in hot springs country, and our water ( well water) has a high mineral content and has a high pH. If you rely on a water softener remember to deploy the bypass button on your water softener tank. If you do not use one, have a sample of your water and soil analyzed.
    I acidified some of the area in my yard and the fruit feee are thriving now. I am probably at too high an elevation for guava, but I’m going to give it a try. Hope this helps.
    Daniel.

    Daniel
  • Bill, I would just continue caring for them like the others, and once they get their roots established, they should catch up to the others. Keep any fruit picked off of them until next year. You want them to put their energy into growing a strong root system the first year and not fruit. Don’t put a lot of nitrogen on them this late in the season. You can fertilize with something that does not contain nitrogen.

    Suzanne
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