Apple Tree Harvest & Yields

How much apple tree yield per hectare or acre?

Apples are among the most popular and produced fruits globally (in the top 3-4), with the biggest producer countries being China, Turkey, and the USA. In addition to their commercial cultivation, apple trees are also a favorite choice for home gardens because of their tasty fruits.

Apple tree yields vary significantly depending on the variety, the tree age, and the management practices applied in the orchard. Mature apple trees (around 6-20 years old), in traditional orchards typically produce between 100 to 800 apples annually or 10 to 50 tons per hectare (8094-40468 lbs. per acre). Dwarf trees, due to their smaller size, yield less per tree but allow for higher planting density. Additionally, the application of modern techniques can lead to enhancing yields, reaching 40-70 tons per hectare (32375-56656 lbs/acre).

Some of the most productive varieties that are commercially cultivated are the:

Gala: A consistently high-yielding variety, popular in commercial orchards for its productivity and market demand.
Fuji: This variety is known for its large, crisp fruits and high yields, especially in high-density orchards.
Honeycrisp: A variety chosen for its flavor and high yield, particularly in cooler climates.
Granny Smith: It is an adaptable variety that offers good yields and apples with tart, a bit sour flavor and firm, crisp flesh.

These varieties perform well with proper care, nutrient management, and high-density planting systems.

Estimating Apple Yields Estimating yields involves counting the number of fruiting clusters and assessing the average fruit size. Penn State Extension provides guidelines for estimating apple yields, which help in planning harvest and marketing strategies. Accurate yield estimation enables better decision-making and resource allocation.

To maximize apple yield, a grower must consider several key strategies. First, choosing the right variety and rootstock based on local climate and soil conditions is crucial. Regular pruning, precise irrigation, and nutrient management (particularly nitrogen and potassium) are vital to tree health and fruit development. High-density orchard systems are also preferred for maximizing yield per hectare/acre, as they facilitate better light and air penetration and application of agrochemicals, which improves both fruit quality and quantity. Lastly, regularly monitoring and managing pests and diseases is essential to prevent yield losses.

Fruit thinning in apple trees

Fruit thinning in apple trees is a crucial horticultural practice that involves selectively removing some of the developing fruits to enhance overall quality and size. By reducing the number of apples per cluster, trees can allocate more resources—such as nutrients and energy—to the remaining fruit. This results in larger, healthier apples with improved flavor and color. Thinning also helps prevent issues like branch breakage due to excess weight and reduces competition for sunlight, air circulation, and nutrients among the fruits. Ideally, thinning should occur when the apples have a diameter of 2-3 cm (0.78-1.18 inches), allowing growers to make precise decisions about which fruits to keep for optimal harvest outcomes.

When and How to Harvest Apple Trees

Harvesting apples is a crucial aspect of apple cultivation that directly influences fruit quality and marketability. Understanding when to harvest and the methods to do so can significantly impact the outcome of your apple production.

Apple Tree Harvest & Yields

Identifying the Best Time to Harvest - When it is Best to Harvest Apples

The timing of apple harvest is vital for achieving optimal taste and texture. Generally, apples are ready for harvest in late summer to early fall, depending on the variety and local climate. To determine if apples are ripe, several indicators can be observed:

Color Change: Most apple varieties change color as they mature. Red apples develop a deep red color in their skin, while green varieties may become more yellow-greenish. To define how the color progresses and when the best moment to harvest the fruit is,you can use a color chart (suitable for the different varieties). - The seed color could be an extra indication. More specifically, the seeds inside a ripe apple change from white to brown.
Size: Size is another important quality characteristic of apples that can define their price range. Farmers can use a caliper to measure the diameter of the apples. Keep in mind that each apple variety has an ideal size range for marketability.
Firmness: A ripe apple should feel firm but not hard. To determine that, you can gently squeeze the apple or use a penetrometer for more accurate measurements. This device measures the firmness of the fruit in pounds per square inch (psi). Ideal firmness varies by variety, but most apples should register between 10-15 psi when ripe.
Sugar content: In commercial apple orchards, growers may use the “starch iodine test,” which measures juice brix. Ripe apples have a brix of at least 12-13. More information about this technique can be found here.
Ease of Picking: Ripe apples typically detach easily from the tree. A simple twist and lift motion should allow the fruit to detach from the branch with little resistance (without squeezing and bruising it). This is especially important for the mechanical harvesting of the fruits.
Taste Test: Perhaps the most subjective method, tasting the apple, can provide immediate feedback on its ripeness. A sweet, flavorful apple is a good sign that it’s ready for harvest.

Methods of Harvesting Apples - How to Harvest Apples

Once you’ve determined the right time to harvest, the next step is choosing the appropriate method. There are primarily two methods for harvesting apples: hand-picking and mechanical harvesting.

By Hand

This traditional method involves picking apples from the tree by hand. It is labor-intensive but allows for careful selection, reducing damage to the fruit. Hand-picking is ideal for smaller orchards and is often preferred for high-quality varieties. It enables the picker to assess each apple for ripeness and quality, ensuring that only the best fruits are collected. The growers may need equipment such as ladders to reach the tallest branches.

Mechanical Harvesting

This method utilizes machines designed to shake the apple trees, causing ripe apples to fall into collection bins. Mechanical harvesting is efficient for larger orchards and can significantly reduce labor costs. This technique can be more easily applied in high-tensity orchards where the tree has been trained in systems like “Tall Spindle.” However, this technique may lead to more bruising and damage to the apples, which can affect their marketability. As a result, selecting the right mechanical harvester and employing it at the right time is crucial to minimize quality loss.

Market Demand - Apple Quality Characteristics

The market (retailers, consumers, etc.) demands specific quality characteristics for apples, influencing how and when they are harvested. The most important are the following:

Color: As previously mentioned, color is a significant quality indicator. An apple with a vibrant color (depending on the variety) is more appealing to consumers and can affect pricing. Apples, especially those consumed fresh, should have minimum defects (brushes, damage from pests, discoloration, etc.)
Size and Shape: Consumers often prefer larger, uniform apples. Harvesting at the right time ensures that apples achieve their maximum size without overripening.
Firmness and Crispness: Consumers like firm and crunchy apples. Overripe apples may become mealy, which is undesirable in the market, and the fruit can more easily be damaged during transportation, while it also has a shorter shelf-life.
Taste: Sweetness and flavor are critical. Varieties that are picked too early may lack the desired flavor profile.
Storage Life: An extended storage life of the product is a characteristic vital for both consumers and retailers. Apples that are either under or overripe tend to spoil faster, leading to economic losses.

How to Store Apples and Common Packaging Methods

Post-harvest treatments are crucial to help extend the shelf life and preserve the quality of apples. After harvesting, apples are usually washed to remove dirt, debris, and potential pathogens. They are then sorted by size, color, and quality to remove any damaged or diseased fruits. An edible wax coating is often applied to apples to reduce moisture loss, delay ripening, and give them a glossy appearance. Additionally, fungicides or other treatments may be applied to prevent decay during storage. In modern storage facilities, apples are also treated to suppress ethylene production, slowing down the ripening process.

To store apples optimally, they should be kept at a temperature near -1 to 0°C (30-32°F) with high humidity (90-95%) to prevent moisture loss. However, keep in mind that many of the popular apple varieties are chill-sensitive, and physiological damages (such as soft scald) may occur if the fruits are stored in freezing temperatures. Such varieties are Honeycrisp, Granny Smith, Gala, Fuji, Red Delicious, and Cortland and should be stored at 3-4°C (37-39°F).

Apples are best stored in a well-ventilated space to allow proper air circulation, which helps maintain their freshness. Controlled atmosphere (CA) storage often extends apples’ shelf life by adjusting oxygen and carbon dioxide levels. Apples release ethylene gas as they ripen, which accelerates spoilage in other produce, so they should be stored separately to avoid cross-contamination. In optimum conditions and if the fruits have been harvested at the right moment, apples can be stored for up to 3-6 months (even 12 months in some cases) (depending on the variety), maintaining good quality.

Apples are susceptible to mechanical damage, such as bruising, punctures, or skin cuts, which can lead to decay and decrease the product's marketability. Common packaging methods include crates, cartons, trays, bags, and punnets. The key is to pack apples carefully, ensuring they are uniform in size and quality within each packaging unit. Overripe or damaged apples must be removed during sorting to avoid contamination. Properly filled containers should be stacked carefully to prevent crushing or shifting, which could damage the fruit. Strapping pallets securely helps ensure stability during transportation.

Apple packaging on pallets should be stacked carefully to minimize the risk of falling or shifting. Packages must be stacked tightly and in alignment to support one another and allow air circulation, which is essential for maintaining apple freshness. Avoiding overfilling packages is critical, as this could cause apples to press against each other, leading to bruising.

By maintaining optimum storage conditions, applying appropriate post-harvest treatments, and using suitable packaging methods, apples can be stored for several months while retaining their quality and taste. These practices are essential for ensuring that apples remain marketable, safe, and appealing to consumers.