1.17.2010

Rosa's Pruning Primer: The Mighty Peach Tree

I've been down in Steinbecktown, pruning fruit trees. I missed the last winter's pruning of them (pregnancy!) and consequently, someone else came in and did some desultory hacking and slicing. The trees still bore pretty well, but I can see that whoever did this to dear old Peachy, Professor Plum, Granny and the rest did not have one tiny clue how to prune. (And yes, I have named the trees. But that is just between us.)

I have a few tiny clues, and a book. (How to Prune Fruit Trees by R. Sanford Martin), to which I referred constantly as I worked. It always takes me a little while to get back into the swing of a pruning session, because it is something I do only once a year, and the methods vary from plant to plant. But it is one of my favorite times of the year, when I can see into the tree's canopy, getting down to the clean lines of branch & trunk, finding the slight swelling of wood that denotes the change from last season's wood to this. The delicate fingering of buds, and the questions-is this a leaf bud? A fruit spur? A fruit bud? Did this bear fruit this year?Should I thin this branch out-or this one?
And amidst all the silent ruminations are the tea breaks, when I find myself rubbing my hands together, smacking my lips and saying "Ooh, lovely!" I always feel like I should be wearing a tweed skirt & wellies. 
Open-Ended
My jobs these days are open-ended, raising children as a primary occupation has few closures involved. Meals to make, things to take out and put away. Daily triumphs and losses, but few things that are ever finished. My successes these days are largely measured by the long term growth and development of my two little start-up enterprises. The Littles, Inc. I have learned to deal with the fact that I rarely have the feeling of immediate accomplishment that comes at the end of a project, or a goal finally met.
And that's usually okay, I am glad to be here with my two lovelies. That's why I look at a pruning job with such glee, and really relish the ability to stand back at the end and say, "Done!"  I've decided to write down some pruning tips, for anyone out there with a view toward pruning fruit trees, and for myself, so I can look this post up next winter when I again take up Felcos and pruning saw. 

The Peach
This tree is over 20 years old and subject to peach leaf curl.  It is also the originator of some of the finest peach jam this side of the San Andreas fault line. 
Some things to remember when pruning peaches: few trees benefit from heavy pruning as does the peach. The peach bears its fruit differently than any other type of fruit tree-the fruit appears on the twigs and branches that grew during the past summer, much like hydrangea macrophylla. And although there will be blossoms all along the length of these twigs, only the center third must be allowed to set fruit. Therefore in the midst of shaping the tree, all these twigs need to be pruned back to one-third of their length.
Here's a few over-all principles to keep in mind: 
Balance 
When pruning, you are trying to get the perfect balance between a) beautifully positioned branches that allow sunlight and freely circulating air throughout the tree or shrub, b) leaf producing wood (that's where all the plant's energy will come from) and c) flower/fruit producing wood, where, duh, all the flowers/fruit will come from.


The Three D's

When you first approach a plant to prune it, you must have in mind the Three D's, and prune accordingly.
That's Dead, Diseased and Disoriented. The first two are self-explanatory, the last refers to branches or stems that are crossing or rubbing against each other or growing up through the center of the plant. All these should be pruned cleanly out, not leaving a stub. Also, always prune to an outward facing bud. Trust me on this.
The important thing when pruning is to make your cuts  right above a node, and not right in the middle of stem or branch, leaving sticky-up bits. Plants regrow from the nodes, this is where the undifferentiated cells are in a plant (stem cells) & where new growth will occur. Make your cuts at an angle, sloping away from the node beneath the cut, so that rainwater does not pool in it. 

Getting back to Peachy
In the end, the peach should be funnel-shaped, with the outer branches forming the sloping sides and the center top left open for complete penetration of sunlight. This open center will permit better ripening of the fruit-R.Sanford Martin. I decided to take Mr. Martin's advice, and to prune out the giant center trunk and branch structure of the tree. It had minimal new growth on it, and lower down in the tree was a bad split that had healed over but had left the integrity of the tree badly compromised. Peach wood is brittle and known to drop branches heavy with fruit. Filled with trepidation and a faint whisper of childish glee at getting to use a big sharp tool, I started in with the pruning saw. When cutting branches, be careful to leave the branch collar intact. The branch collar is the distinctive bulge where the branch comes into the trunk, it is actually the interlocking of cells from branch to trunk and will seal off the wound left from pruning.
After I took care of the Three D's, I noticed that there were several vigorous new branches that were growing straight up in the air. I decided to train these into position to take the place of old branches that had been thinned out.  One of the keys to successfully training and pruning fruit trees is the knowledge of the hormonal balance in the fruit tree's branches. It is a wondrous and complex subject and I will only scratch the surface here. (Anyone is welcome to jump in here and add to this.) 
King of the Mountain

The branches of a tree are fighting for apical dominance, which is basically who is going to be the tallest branch on the tree. This is known as the central leader. When the tree is young a central leader is chosen and the rest are pruned out.  If it becomes damaged or old, you might elect another branch to take its place. These vigorous upright branches will generally not form fruit- when a branch is upright the hormonal balance is towards leaf and wood production. If a branch is concerned with taking over apical dominance, it will not want to be bothered with something as calorically taxing as flowers and fruit. These vigorous uprights will also shade out fruit-bearing wood. 
Fruit-Bearing Wood

In order to change one of these uprights into a respectable member of the fruiting branch scaffold, the branch needs to be bent down to a 45 degree angle. This can be accomplished with cotton twine and a stake if the branch is big, or something like weights hanging off the branch. If the branches are supple enough, wooden spreaders are often used. Ole Peachy got the twine and a stake treatment. Once the branch is at 45 degrees, the hormonal balance shifts again into fruiting wood, add to that adequate sunlight and air circulation and you are well on your way to some amazing peach jam.

 Be careful not to let the branch bend down too far, the result is a weak crotch angle and subsequent breakage under a heavy fruit load. 
Peach Leaf Curl

 I mentioned earlier that this tree suffers yearly from peach leaf curl. It seems like I've never been able to get the timing right on when to spray, and with what. Since I was trained using the organic method, and  my mother-in-law's garden shed holds a surprising amount of things that can kill you before teatime, I'm going to try lime sulfur, which I've heard should do the job. The trick is to correctly time the spraying; January before the buds swell is what I am hearing. When I head back down there next week I'll give it a good douse.
Kudos To Two Local Plantsmen
Orin Martin, up at the UCSC Farm and Garden is a master at fruit tree production, and really knows his stuff. He instilled some really great principles of fruit tree training and pruning in me. Even though I apprenticed at the Farm in 2002, I've come up since then for many of his workshops that are open to the local community. It's just so fun to be around him as he darts from tree to tree, snipping here, and whacking there. And I always learn something new. What the heck, here's a link to some info on the Friends of the Farm and Garden, so you can go and learn from the best. And I can't mention pruning without thinking about the incomparable Richard Merrill, who taught me the basics in my Horticulture 1A  and 1B classes at our local junior college. Rich Merrill co-wrote a combination gardening/cookbook with Joe Ortiz, purveyor of awesome yumminess at Gayle's Bakery, a local institution. I wish more people knew about this book, The Gardener's Table, because it is great, and packed with many many veg. growing tips and recipes. Cabrillo's Horticulture Program lost a great director when he retired.
So that's it from me. I only wish I had the presence of mind to take pics whilst I pruned. Instead you must make do with these cobbled together diagrams. Heck, I wish I had the presence of mind to not drop my camera and break it a month ago! Ah well.

6 comments:

Anonymous said...

Don't know if you remember this or not, but the peach tree at the Marnell house had a serious case of curly leaf and produced the largest, juiciest peaches on the block. From what I hear, it is a pretty common ailment for peaches. Ok....so, thats about all I have to add on the subject.

rosa said...

I completely forgot about that peach tree. Yeah, the tree seems to bear alright through the p.leaf curl, but I think the issue is that it opens the fruit up to scalding by the sun? I'm not sure.

Blessed said...

D must wonder what I am reading, as he walked by just as I got to your explaination of the different branch types and how you can retrain them into a different role--I was literally "Ooooooh!"ing and "Ahhhhhhhh!"ing. Fascinating!

rosa said...

Blessed-If you ever want to go to one of the Friends of the Farm and Garden fruit tree pruning workshops, I'm down.

Outdoor Lighting said...

I think I'm going to have to pick up that book. Thank you so much for the very informative post.

Lucy Corrander said...

There is something special about the idea of pruning fruit trees in the same way as there is about the idea of making bread - and there are early-practise failures in both . . . except with bread you can try again tomorrow and with fruit trees it's at least a year before you can have another go (and the consequences of mistakes rather more dire!).

Lucy

Read Your Way Through the Garden: Choice Tomes From Garden Literature

  • A Book of Salvias by Betsy Clebsch
  • Botany for Gardeners by Brian Capon
  • Making Bentwood Trellises by Jim Long
  • RHS Encyclopedia of Plants & Flowers
  • Rose Primer: An Organic Approach to Rose Selection & Care by Orin Martin
  • Start With the Soil by Grace Gershuny
  • Sunset Western Garden Book
  • Sunset Western Landscaping Book
  • The Book of Garden Secrets by Patent & Bilderback
  • The Concise Oxford Dictionary of Botany
  • the Gardener's Table: A Guide to Natural Vegetable Growing and Cooking by Richard Merrill & Joe Ortiz
  • The Gardener's Year by Karel Capek
  • The Hutchinson Dictionary of Plant Names: Common & Botanical
  • We Made A Garden by Margaret Fish

lotsa latin: rosa's botanical & etymological ruminations

  • vespertinus: flowers in the evening
  • vernalis:spring
  • veni vidi nates calcalvi: we came, we saw, we kicked butt. This was printed on a T shirt I bought at Abbot's Thrift many years ago. It encircled the NEA symbol. I wish I knew why.
  • superciliaris: shaped like an eyebrow ex: sturnella superciliaris, the White-browed Blackbird
  • rosa-sinensis: species of Hibiscus: Hibiscus rosa-sinensis. Lit. Rosa of China, so named by British plant hunters.
  • placentiformis: shaped like a cake ex: discocactus placentiformis
  • nudiflorus: flowers before leaves show ex: flowering quince, magnolia
  • nivalis: growing in or near snow ex: galanthus nivalis (common snowdrop)
  • muralis: growing on walls
  • mirabilis: marvellous, wonderful
  • formosa: beautiful ex: dicentra formosa, a.k.a.western bleeding heart/dutchman's breeches/lady in a bath
  • carpe vitam: get a life
  • Carolus Linnaeus: Latinized name of Carl von Linne (1707-1778), Swedish naturalist considered the father of plant taxonomy. Whatta guy.