June is an important time for some key orchard care tasks including fruit thinning and pest and disease management practices. And June is of course when many of our early orchard harvests begin! 

Please check out our new POP Monthly Orchard Task List for recommended maintenance activities to complete this month. Here is some more detail on some of the key tasks for June: 

Check out the Spring orchard care video POP produced last year on fruit thinning, and read more below.

Fruit Thinning Time! 

By late May to early June, small fruitlets have formed on most fruit trees and it’s time to thin them out. All fruitlets should be removed from young trees planted this spring or last fall to allow the tree to focus its energy on getting established. FOR APPLES, PEARS, PEACHES, and sometimes PLUMS and APRICOTS: these fruit trees need to be thinned throughout their lifespan. Apples, pears, and Asian pears should be hand-thinned to 5″ apart on the tree, peaches to 8″. Some plum and apricot trees with heavy fruit set should also be thinned to a few inches apart to avoid the risk of branches breaking under the weight.

A hand, its thumb and pinkie finger extended, provides a “handy” ruler you can use in the field for fruit thinning.

Fruit thinning is important to produce the best quality and size of fruit, and helps reduce problems with common diseases like brown rot and insect pests like codling moth. It also helps reduce alternate bearing, which is the tendency of some trees to produce large harvests one year and little or no harvest the next. Read more: 
Fruit Thinning
Recipes for Unripe Thinned Plums

As you’re thinning your stone fruits, be sure to remove any showing signs of brown rot (or any other pest or disease damage)! 

Pest and Disease Monitoring & Identification
NOTE: We’ll be demonstrating a wide range of pest and disease management practices including emergency pruning, fruit thinning, bagging, beneficial insect releases, and more at our upcoming hands-on POPCORE workshop on 6/12.  

Spring is when many pest and disease challenges show their first signs!  Some of the most common insect pests to contend with in June include: 
Oriental Fruit Moth
Spotted Lanternfly
Plum Curculio
Codling Moth

Curling leaves and/or ants in your tree are signs of aphid infestation. 
For severe outbreaks, consider a neem oil spray, as featured in POP’s new spring orchard care video.  

Observe your orchard regularly throughout the year for pest and disease problems, identify and respond appropriately.  We’ve begun distributing physical copies to community partners, but in the mean time you can check out our POP’s Scouting Guides for pest and disease management available for download on POP’s website: 

These guides are intended to help properly identify the insect pests and diseases that effect the following common fruit trees: 
Plums (& Apricots)
Pears & Asian Pears
The guides include lots of photos and a description of how to identify the particular pest or disease and the damage caused by it.  Proper identification is essential to treating these problems, as each has its own unique options for management!  Once you have identified a pest or disease, you can then consult our website for management recommendations by using our search function: 

17 Year Cicada Alert!
POP was not in existence in 2004, the last time Periodical Cicadas were active in Philadelphia, but apparently they can sometimes cause damage to fruit trees. Trees younger than 4 years may need protection (netting is recommended) once the cicadas emerge. You will know the adult cicadas are active when you hear the high-pitched whine of the male insects. You can read more about cicadas as orchard pests in this article from PSU Ag Extension.

Please report back to POP if you do see any cicada damage on your trees.

Fruit Bagging
June is a good time to protect young fruits from pest and disease through the practice of fruit bagging.  This simple technique is most commonly used for apples, pears, and Asian pears and can help protect from common pests including apple maggot, codling moth, and more without the use of sprays. Read more about fruit bagging here: 

Fruit bagging can be done with ziplock baggies or nylon footies! 

Spring Orchard Sprays 

Depending on specific pest or disease problems, some orchardists may consider  organic sprays including the ones listed below. Check out POP’s guides to orchard applications of:

Compost Tea Sprays for Orchards
Neem Oil Sprays
Kaolin Clay Sprays
Sulfur Sprays and Early Spring Management Techniques
Pyrethrin Orchard Sprays
Bt: Bacillus thuringiensis Orchard Sprays
Spinosad Orchard Sprays

Spring Weeding and Compost/Mulch Application

With the wet weather and warming temperatures, many weeds are growing rapidly.  Time to get out there and edit the plant palette!  POP’s weed identification guide is available for sale on our website and we always have free copies to distribute to community orchard partners. 

Building healthy soil is key to supporting trees’ health, resilience and yields. Weed around the base of trees, and spread at least one or two inches of chipped winter prunings, shredded leaves, and/or mulch or compost in the spring. Check out POP’s guide to Ramial Wood Chips and Weeding in Place.

Fireblight Removal and Emergency Pruning

With dormant season well behind us, most pruning should be limited to emergency pruning only.  

Keep an eye out for any diseased, damaged, or dead wood that should be pruned away no matter the season. Pay special attention to the base of trees – especially of the stone fruit varieties: apricots, peaches, plums, nectarines – and prune away root suckers, the quick upright growth that can be a cover for dreaded borers, which make a home beneath trunk wood. 

Keep an eye out for fire blight damage on apples and pears in June.  Be sure to prune back to healthy wood at least 8 to 12″ below signs of damage to prevent further spread of this disease. 

Remember: use sharp, rust-free hand tools and sanitize between every cut for disease prone trees during the growing season. For easy disinfecting, we recommend carrying a spray bottle with you of rubbing (isopropyl 70%) alcohol or a bleach solution (1 part bleach: 10 parts water) to wipe down tools.  

Spring Harvests!
Juneberries, strawberries, and goumis are already ripening, to be followed soon by raspberries, cherries, mulberries, currants, honeyberries, and more! 

Enjoy the spring harvests and join us for an upcoming POPharvest event of juneberries or mulberries!  

This POP Blog Post was written by POP Co-Executive Director Phil Forsyth, and re-edited for blog posting by POP Intern Joe Dizenhuz

SUPPORT US!  If you found this entry useful, informative, or inspiring, please consider a donation of any size to help POP in planting and supporting community orchards in Philadelphia: phillyorchards.org/donate