To Be Successful, There Are A Few Important Things…
There are a few secrets one must know in order to grow growing peaches and other tender fruits in the colder zones of the US. While we pick the hardier varieties of peaches, such as Veteran and Reliance, we do grow more tender versions of them, as well, and we need to modify the standard plant, fertilize and prune practices of most orchards.
We have apricots, sweet cherries and European plums that all fall into the “tender” categories; however, the largest number of these are our peaches. We are collecting peach pits from local peaches and planting them out to find even hardier varieties that work well in Zones 4 and 5. But even those will need to be handled differently from your standard, cold hardy apple tree.
It’s Not Just The Cold…
What we’ve found is that hardiness is more involved than just how cold it gets. This is only one determining factor that determines the life of a peach tree. My own shock at Maine winters and the pure cold that is encountered, is the same cold that is most attributed to the death of peach trees. Zone 5 in Southeastern Massachusetts is different than Zone 5 in Winterport, Maine. However, there is more to killing tender trees than pure cold. Snow cover, warmth of days vs. nights, where they are planted, fertilizing during summer are just a few issues that affect tender trees.
How Autumn Influences Tree Dormancy…
The change from a growing tree to a dormant tree is usually gradual with hardier trees tending to enter dormancy earlier in the season than tender trees do. Often, trees are credited with death due to a very cold winter where in fact they died when the weather changed quickly from warm to cold in fall. Trees that go into dormancy later, like a peach, may be adversely affected when this happens. Also, temps that drop below freezing for an extended time early in the season and then back to warm hurt the tree as well.
The last thing to harden off is the trunk. Where we hear reports of the branches not surviving, the real issue is the trunk. We have an apricot that died back to just above the soil line last year which was one of those warm/cold/warm winters. In fact, winters that hover above and below freezing have killed or injured more trees in our orchard than really cold winters.
The peach shown here with leaves still on it in December will be watched closely next year. We realize that this tree is probably being affected by the waste water line keeping the soil warm which, in turn, is giving the rootstock false reading as to what the weather is really like. The tree will be moved next spring.
SouthWest Injury and How it KILLS Peaches…
Another big issue is southwest injury. On a mid winter’s day, the southwest side of the tree warms up from the sun shining on it, even though it’s quite cold out, the low angle of the sun hits the side of the tree perfectly to warm it. Then, a cloud comes by or night hits and, boom, you’re back to below freezing. Do this over and over until you’ve killed the cambium layer on the southwest side of the tree. The further north you are, the more dangerous to your trees this is.
To protect against southwest injury, you must either paint that side white, put a tree guard on (but take off in spring to avoid pest injury), or increase the planting of shrubs on this side to protect the trunk from even getting the sun. We’ve done a combination of these things and plan on increasing the number of shrubs planted this year. Anything that keeps the sun off this side of the tree is going to help get your trees through the winter. This photo shows the plantings to the southwest that help protect the trunks of these dormant Reliance Peaches.
When planting tender trees, keep them in a shade source for the winter, just to keep the sun off of them. Do NOT put in a “safe” place, i.e, Southern exposure and protected, like against a wall, this actually increases winter kill and early blossoming. Plant them on the north side of anything that will provide shade in winter and sun in summer. This keeps them deep in dormancy. As long as they are dormant, they should survive winter even in areas that they are not rated for.
Do NOT Fertilize Tender Trees!
First off, never fertilize fruit trees, especially young ones. Most fruit trees, if planted in good soil, do not require fertilizer. If you have poor soil, build your soil with fungal compost, add chopped leaves and mulch. Good soil will feel your tree. Fertilizer keeps the tree, preventing it from recognizing natural cues to go dormant. This can cause shock, injury and death to the tree when winter hits with full force, sometimes with little warning, in northern climates.
We will cover this fully in another tutorial; however, it is also good to note that fertilizing DOES slow down the maturation and fruit bearing properties.
One More Thing…
One thing to remember when growing peaches, apricots and nectarines is that these are not long lived trees, even in areas where they thrive, they are not a tree that will produce for your future grandchildren. We look at planting some every year at our orchard and mix them in with other trees for protection. We’ve chosen the most hardy peaches for our nursery at Winter Cove Farm.
Remember these and you’ll grow peach trees AND actually eat them every year.