Shortly after tree growth begins, gently remove the 3 developing shoots below the leader to eliminate competition for leader growth. Photo: Tara Baugher
Some growers were able to take advantage of an early window for planting fruit trees in February while others are just now completing their planting of new orchards. Depending on where you are with your planting season, you will start at a different place on the following check list. Simplified tree training strategies decrease the need for time-consuming bending of limbs later in the season or next year. Timely orchard floor, irrigation, pest, and nutrition management promote optimum tree growth.
With support from a USDA-NIFA beginning farmer grant, "Models for the Future" apple plots were planted in locations around the state this spring. This planting is in Berks county, and the grower cooperator is Jake Scholl. Following two years of bio-remediation, a slow growing endophyte-enhanced fescue mix was planted in fall 2016. The well-established sod will out-compete broadleaf weeds that may serve as reservoirs for viruses associated with tree decline. Photo: Jake Scholl
Tree training following planting
- Remove all feathers below 24 inches using a flush cut, just outside the collar at the base of the shoot.
- Begin training the tree to a conical tree form using "tall spindle" training strategies presented in a Penn State Extension "Learn Now" video titled The Apple Orchard System Blueprint.
- Remove any feathers that are larger than two-thirds the diameter of the leader, leaving a short stub for limb renewal.
- Avoid heading cuts, as removing the apex of either the leader or the laterals results in increased vegetative growth and reduced fruit bud initiation.
Tall spindle training system. The goal is for the tree to reach the top wire by the end of Year 2 and for a fruiting wall to be in place in Year 3. Photo: Tara Baugher
Simplified rules based on "Science of Pruning" research
Our research on the science of pruning indicates that pruning and training requirements are simplified by strategic removal of excessively vigorous limbs. The studies also show that the stub does not need to be cut to a beveled angle.
Example of a renewal limb that developed as a result of a stub cut that removed an overly vigorous limb. Photo: Tara Baugher
Timely integrated pest and cultural management
- Immediately begin an integrated program to manage rabbits, voles, deer, insect and mite pests, diseases, and weeds.
- Install tree guards and follow the disease, insect, and mite management programs in the Penn State Tree Fruit Production Guide. In scouting your block, monitor closely for apple scab along with foliar-feeding insects that inhibit early tree growth. Also monitor for early signs of deer browsing and dogwood borers.
- Maintain a 4-ft wide herbicide strip in the tree row to prevent competition for nutrients and water. Research shows that orchard floor management can influence early tree growth more than fertilizer application.
- After the ground has settled and the trees have started to grow, apply 2 to 4 ounces of calcium nitrate per tree in each of two split applications, a month apart.
- Use caution to prevent contact of fertilizers or herbicides with young bark on the trunk.
Wide herbicide strips encourage early tree growth, while thick sod middles discourage the establishment of broadleaf weeds that may attract bees away from apple flowers or serve as virus vectors. Multiple applications of low rates of calcium nitrate are likely to be more effective than a single application. Photo: Tara Baugher
Timely installation of support and irrigation systems
- Install a wire trellis that will allow the tree to be supported to 9 feet. Early growth is improved when a tree is immediately tied to a support system.
- Attach the trees to the lower wire of the support system with a permanent tree tie.
- Install drip irrigation. Last season's drought was a reminder of the importance of having the capacity for supplemental irrigation.
The permanent tie should be attached to the wire in a manner that prevents tree movement, and it should allow space for trunk expansion. Photo: Tara Baugher
Early tree training steps
Early tree training steps will reduce labor-intensive limb bending later in the season.
- Shortly after bud swell, rub off the 3 shoots below the leader to eliminate competition for leader growth.
- Also remove any flower buds that are present - this is especially important with weak growing trees, a common problem in Honeycrisp. Remove the buds before they open to reduce fire blight risk.
- Vigorous cultivars may require a second trip through the orchard to remove upright shoots below the leader when they are 3 to 4 inches in length.
- Throughout the remainder of the season, continue to tie the leader to the support system.
- If any laterals are excessively long or upright, bend them to a more horizontal position. If you were diligent about removing upright and large diameter limbs at planting, this training can be kept to a minimum.
Removing the 3 shoots below the leader can save considerable labor later in the season and in subsequent years. Where buds have recently emerged, they can be easily rubbed off with the thumb and fingers. When the shoots are about three inches long, they can be gently removed with a downward pull. To avoid fire blight, be careful to only rub off flower buds when they are still at the pink stage or earlier. Also avoid training trees during a fire blight infection period. Photo: Tara Baugher
Planting intensive orchard systems and adopting practices such as minimal pruning and simplified training are fundamental components of a successful "blueprint"for an orchard with the highest market quality and production efficiency.