If you are a plum fan, you’ll be delighted to know that they are easy to grow in most of the United States. Do you live within USDA hardiness zones three through eight? If so, you can harvest homegrown plums in no time.
Before planting, you’ll want to ensure you set your trees up for success. The right fertilizer for plum trees delivers the nutrients for a bountiful harvest.
But how do you know if a fertilizer is right for your plum tree, let alone if it’s the best fertilizer for plum trees? Keep reading, and we’ll give you the scoop on plum tree fertilizers!
Our Top Picks
Best Overall:
Hoss Complete Organic Fertilizer
Best for Young Trees:
Jobe’s Fertilizer Spikes for Trees & Shrubs
Best for Mature Trees:
Dr. Earth Flower Girl Bud & Bloom Booster
Our Picks for the Best Fertilizer for Plum Trees
So now that we’ve brought you up to speed on the basics of plum tree fertilizers, let’s dive into the list of our favorite products to recommend!
Best Overall
Hoss Complete Organic Fertilizer
The best organic soil amendments are derived from organic compost and manure. Hoss Organic Fertilizer is made with chicken manure, an excellent nitrogen source. This certified organic formula delivers an outstanding balance of key nutrients for plum trees and supplements with calcium to help with fruit production.
Pros:
- Certified organic
- Includes calcium
Cons:
- Somewhat expensive
Best for Potted or Young Plum Trees
Jobe’s Fertilizer Spikes for Trees & Shrubs
Some types of plum trees make excellent container plants. Fertilizing potted trees can sometimes be a challenge. You must carefully dose fertilizer for potted plum trees to prevent nutrient burn. Jobe’s Fertilizer Spikes deliver a slow, steady supply of essential nutrients.
For the young plum tree, foliage growth is important. These spikes are high in Nitrogen which will promote foliage growth.
Pros:
- Releases nutrients slowly
Cons:
- Large trees need many spikes
Best for Mature Trees
Dr. Earth Flower Girl Bud & Bloom Booster
Dr. Earth Flower Girl Bud & Bloom Booster is ideal for a mature plant that might need help with blooming and fruit production.
Pros:
- Ideal N-P-K ratio suitable for all stages of growth
- Extra phosphorus for healthy fruit development
- Includes mycorrhizal fungi
Cons:
- Somewhat expensive
Hoss 20-20-20 Garden Fertilizer
Fruit trees need a balanced diet of essential nutrients to fuel annual growth. This high-quality fertilizer has equal parts nitrogen, phosphorus, and potassium, plus micronutrients. Once your tree is well established, this should be your go-to fertilizer for mature plum trees.
Pros:
- Balanced N-P-K ratio
- Includes additional nutrients to promote healthy growth
Cons:
- Somewhat expensive
FoxFarm Happy Frog Cavern Culture Dry Fertilizer
Fertilizers for plum trees should have extra phosphorus to encourage healthy fruit development. If you already have relatively balanced soil, you may just want to add this FoxFarm high-phosphorus fertilizer in summer before your plum trees go to fruit.
Pros:
- Excellent source of phosphorus for fruit production
Cons:
- Very low in nitrogen
- Contains no potassium
Plum Tree Fertilizer Basics
All fruit trees require essential nutrients for foliage and fruit production. Luckily, figuring out the proper nutrition for your trees is simple once you understand the basics. Are you new to growing plum trees? Start by checking out our guide on How to Grow Plums.
Fertilizer contains three primary elements: nitrogen, phosphorus, and potassium. The amount of these ingredients is called the N-P-K ratio, denoted on the fertilizer packaging with three hyphenated numbers. For example, 10-10-10 fertilizer contains equal parts of nitrogen, phosphorus, and potassium, respectively.
You should always use a soil test kit before adding any fertilizer. Soil testing gives you the actual nitrogen level of the native earth, so you can amend it appropriately. Adding too much nitrogen can cause excessive growth. While this might sound good, explosive vegetative growth at the wrong time will hinder fruit development.
Using organic matter, like aged manure, you can create DIY fertilizer for fruit trees. You should test homemade fertilizer with a soil test kit before applying it to young trees. You want to ensure you are supplying young plum trees with adequate nutrients required for tree growth.
Mature trees are more forgiving when it comes to fertilizer types. Still, boosting the soil with phosphorus at just the right time can bolster fruit growth. Furthermore, some soil additives protect developing fruit from common nutrient deficiencies.
Test soil samples if you notice abnormal or slowed growth to ensure your trees have sufficient levels of macro- and micronutrients. Trace nutrients like calcium and boron contribute to healthy fruit production. Consider adding a supplement like Hoss Micro-Boost, which contains essential trace nutrients.
The best fertilizer for plum trees enables you to achieve maximum fruit production in your orchard. Plus, by paying careful attention to macronutrients, you will harvest the most delicious fruits you’ve ever eaten.
How to Apply Plum Tree Fertilizer
You can fertilize plum trees the same way you fertilize any fruit tree. Always read the instructions on store-bought amendments to learn how much fertilizer per inch of trunk diameter is needed.
Start with a soil test to determine the pH and fertility of your planting location. Note that plum trees prefer slightly acidic soil. After soil testing reveals current soil conditions, you can resolve any nutrient deficiencies or pH imbalances.
Most experienced arborists fertilize plum trees in split applications. Consider only an annual application in spring if the local soil is especially rich. Exercise caution when fertilizing plum trees close to winter dormancy. Doing so can spur late growth that is susceptible to frost damage.
Step 1: Conduct a Soil Test
To create the best soil for plum trees to grow in, you need to understand the fertility of your local environment. You must conduct a soil test before adding any fertilizer. If you don’t, you could risk harming your young plum trees.
Additionally, you won’t detect major nutrient deficiencies that impact fruit production without a comprehensive soil test. Healthy soil that is fertile and rich in trace nutrients will ensure prolific harvests of delicious plums.
You need to purchase a soil test that detects micronutrients and pH levels alongside the N-P-K ratio. This is essential for achieving the best fruit growth. Nutrient deficiencies often deeply impact fruit quality and production.
Plum trees are especially susceptible to boron deficiency, which shows up in the fruit. Low boron causes mushy dead spots in plums and low fruit production. You can supplement the soil with borax to increase boron levels.
Iron deficiency causes chlorosis in plum trees, which significantly impacts photosynthesis. The most notable sign of chlorosis is the yellowing of the leaves contrasted by green veins. Add chelated iron to prevent or treat this deficiency.
Step 2: Apply Plum Tree Fertilizer to Drip Line
Are you applying store-bought fertilizer? If so, follow the instructions on the label to properly fertilize your plum tree planting location. Too much fertilizer can injure your tree, so read the directions carefully.
Do not apply any fertilizer near the tree trunk. Instead, leave four to six inches of space around the trunk clear of any mulch, fertilizer, or other additives.
The drip line is the furthest that mature leaves extend out beyond the trunk. Be mindful of future tree growth as you fertilize young plum trees. It is recommended to extend fertilizer application past the current drip line for trees that are still growing.
Step 3: Water Thoroughly
Plum trees need to be watered frequently, especially after applying fertilizer. Adequate moisture combats complications like nutrient burn and allows the fertilizer to be absorbed evenly throughout the roots.
Additionally, many of the best fruit tree fertilizers are water-soluble. They should be well saturated after application so the nutrients can soak deeply into the soil. This will ensure that the tree will continue to benefit from fertilization well into the season.
FAQ
Is 10-10-10 a Good Fertilizer for Plum Trees?
10-10-10 fertilizer contains equal parts nitrogen, phosphorus, and potassium. This ratio is ideal for many applications, making it an all-purpose fertilizer blend. You can supplement mature plum trees with 10-10-10 fertilizer, but always test the soil composition before adding fertilizer of any kind.
Why are the leaves on my plum tree going yellow?
Plum tree leaves turn yellow when there isn’t enough iron in the soil. Iron deficiency causes chlorosis in plum trees, which can be identified by yellow leaves with green veins. You can prevent and treat chlorosis by supplementing the earth with chelated iron.
How often should you fertilize plum trees?
Fertilizer for plum trees should be applied twice per year. The first application of high-nitrogen fertilizer can be added in early spring to support green growth. Supplement the soil with phosphorus once your plum trees shift to the fruiting and flowering stage.
A Guide to Fertilizing Plum Trees
Finding the perfect fertilizer for plum trees is straightforward. As long as you know the composition of your local soil, you can pick the proper amendments to help your plum trees flourish. Excited for more plum content? Then check out our plum trees page for the latest growing tips, care guides, recipes, and more!
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