Tag Archives: pruning tips

Fruit Tree Care – Fertilization & Summer Pruning

Whether you grow one fruit tree or a home orchard full of them there is always something to learn from an expert and Orin Martin of UCSC Farm and the Alan Chadwick Garden is just the guy to help. With nearly 40 years of hands-on experience at UCSC he says he?s come up with a successful method of caring for fruit trees including pruning and fertilizing . ?I?ve made every mistake in the book?, he laughs.

Orin_Martin_prunig_fruit_trees
Orin Martin explaining summer pruning

The UCSC Farm and Alan Chadwick Garden on the campus are both internationally known for training, research and public education. Recently I had the opportunity to join Orin during the Summer Orchard Walk at The Farm as he discussed the care of fruit trees and summer pruning to improve tree shape and productivity. Between jokes he shared many tips including the importance of fertilization and preparing an orchard for fall and winter.

Deciduous fruit trees are genetically programmed to start root growth early as they originated in the cold winter climates of Northern Iran, Uzbekistan and other central Asian areas. Their growing season begins in January or February which is 3-5 weeks prior to any visible bud swell when soil temperatures are still in the low 40?s. With this in mind Orin recommends starting fertilization early. Organic fertilizers take longer to become available to the tree and you want to maximize the early growth spurt in spring.

sunflower pollinator attractors
Sunflowers attract pollinators to garden

Orin has a recipe for fertilizing young fruit trees that is used throughout the Farm and Garden. It?s comprised of compost and an organic source of nitrogen such as blood meal, 8% Nitrogen Sustane or Dr. Earth granular. A young tree will need additional nutrients in May and possibly July if the tree is not putting out sufficient structural growth. Fast acting liquid fertilizer such as fish emulsion and liquid kelp can be substituted for the early summer feeding. The second wave of growth occurs in fall. Slow acting organic fertilizer is best at this time.

Next year?s fruit buds are formed in late spring to early summer at the same time current fruit is growing so nutrient needs are extremely important at this time. If a mature tree is growing well its yearly fertility needs may be met by growing a bell bean crop as green manure over the winter.

Ginger_Gold_apples
Ginger Gold apples with resident cats

The two resident garden cats followed our group as Orin demonstrated summer pruning of Ginger Gold apples, Flavor King pluot and Seckel pears. Most are trained to a open center with some having a modified central leader. I asked what he would do if no central leader grew after heading back a young tree whip. ?Then I?d train it with an open center. You?ve got to play the hand your dealt?, he laughed.

?Ladderless? harvesting and care is the goal to pruning in summer and winter. Summer pruning from early August to mid September stops growth and is done to limit height and length of branches to encourage more fruiting shoots. Winter pruning creates the tree?s structure. ?When you don?t want a tree any taller, stop winter pruning?, Orin told us.

UCSC Farm_Garden_crops
UCSC Farm crops

Throughout the orchard walk Orin Martin shared interesting tidbits of information. Seems that pest problems such as European blister mite and pear slugs are being observed here at for the very first time.

The USCS Farm & Garden has free monthly guided tours as well as a calendar of educational talks and events. It is open daily for everyone to learn and enjoy. Kids tours are offered during the school year in the Life Lab Garden Classroom.

Do I Really Need to Dormant Spray and Prune my Fruit Trees?

Gummosis canker on dwarf nectarine- Photo courtesy of Sherry Austin
Gummosis canker on dwarf nectarine- Photo courtesy of Sherry Austin

A Facebook friend recently posted a picture of gummosis on her dwarf nectarine. While pruning her fruit trees she found the sticky stuff and shared her plight. While some folks post pictures of babies and political opinions on their Facebook page, my friends post pictures of plants and their fruit trees. Yes, if you haven’t already done so, this is the time to winter prune fruit trees and apply dormant spray to fend off diseases and insect pests. With rainfall expected throughout the spring this is not the year to omit this important task.

Why prune your fruit trees in winter? The reasons to prune fruit trees are to increase fruit production, develop strong 45-degree branch angles to support fruit load, remove limbs that grow down or straight up, maintain tree size and maintain fruit spurs. The dormant season is the best time to train a fruit tree during its first three years. Pruning trees during the dormant period tends to have an invigorating effect on the tree. Good for a young tree, not so good if you are trying to control size.

Gummosis on plum in summertime
Gummosis on plum in summertime.

Pruning of dead or diseased branches can be done anytime, however, the sooner the better. And don’t prune suckers in the winter. This insures they will grow back in the summer. Over zealous winter pruning can result in waterspouts so go easy at this time of year. Summer pruning, done in June or July, decreases size and vigor which helps to slow the growth of a tree.

Often I’m asked whether to paint a wound with sealing compound after pruning. This is no longer recommended as it encourages wood rot. A tree is best protected by proper pruning technique and timing. With this in mind, don’t prune during late spring or fall as a tree is most vulnerable during those times. When you cut away part of a plant, a would is left, susceptible to pests and diseases. To avoid trouble always prune so as to make small wounds, rather than large ones. Trimming a bud or twig produces a smaller wound than waiting until it is a large limb. Rubbing off a sucker bud leaves a smaller wound than if you want until it has a year’s growth or more.

My friends sticky amber gum oozing from her dwarf nectarine branch is the tree’s reaction to stress. Cankers or sunken lesions covered with gum may be caused by mechanical injuries, such as lawnmowers or pruning, insects, winter damage, sun scald, herbicide injury or various fungal or bacterial infections. Practice good sanitation by removing and destroying cankered limbs.

You can prevent or control many diseases and overwintering insects by applying a dormant spray this month. This can be the most effective spray of the season. Fungal diseases such as peach leaf curl, fire blight, scab and anthracnose as well as insects including aphids, San Jose scale, bud moth, leaf roller, coddling moth and whitefly larvae, mealybugs and mites can all be controlled.

There are several types of dormant sprays and all three types are considered organic. Lime-Sulfur or copper can be mixed with horticultural oil which smothers overwintering insects and eggs. This spray is good for all fruit trees except apricots which should be sprayed in the fall with copper and this month with horticultural oil.

Apply dormant spray when the temperature is above 40 degrees. Make sure you cover every nook and cranny of each branch and trunk until the tree is dripping and spray the surrounding soil. Spray only plants that have suffered from pests or disease. Sprays, even organic, can kill beneficial insects as well. Even though they’re organic, dormant sprays can be irritating to skin and eyes, Wear long sleeves and gloves and eye protection.

I hope I don’t find any pictures on Facebook of your plant pests or diseases but post away if you something wicked your way comes and I’ll try to help.

?Pruning Roses- How, When & Why

 

Mixed rose bouquet
Mixed rose bouquet

In between storms I’m itching to get outside and do something in the garden. It’s too early to cut back the perennials as some frosty nights are sure to come our way between now and mid-March. But it’s just the right time to start pruning the roses. It’s best to prune your roses before they start leafing out or some of their energy will be wasted.

Last year, mine were looking just fine in January, thank you very much, so I thought I’d skip the pruning and removing last year’s leaves. Boy, what a mistake. Oh they looked great in January and February when there was no precipitation. Then some rain fell in March. I’m not kidding when I tell you that every single leaf got black spot and rust. My rose varieties are usually resistant to disease but they could not fight back against the fungal spores lurking in the soil just waiting to colonize those old leaves.

Yellow fragrant rose
Yellow fragrant rose

Roses give so much back I think they are worth the extra mulch and a little extra water to keep them producing those lovely blooms. There’s nothing quite as dramatic as a mixed bouquet of scented roses on the table.

I want my rose bushes to produce lots of roses on a compact shrub and not just a few exhibition size blooms so I prune my shrubs moderately. My goal is to keep the center of the plant open for good air circulation aiming for a vase-shaped bush with an open center. I’ll cut out canes that cross, saving the better of the two, prune spindly and diseased stems and dead wood. I’ll also prune canes that appear weak or broken. Healthy canes appear green or reddish while old and dying canes are brown. Then I’ll cut back the remaining stems by about third. When pruning cut canes at a 45-degree angle just above an outward facing leaf bud or a swelling on the cane. Slant the cut away from the bud to encourage growth outward. Clean pruners afterward to prevent the spread of disease and keep your pruners sharp to make clean cuts.

Same goes for climbing roses. Cut out extra stems if there are too many and also cut back long established canes to the place where they are slightly thicker than a pencil. Then cut each side stem down to several inches. This will cause the cane to flower along its complete length for a beautiful spring display.

Bouquet of mixed roses
Bouquet of mixed roses

Heirlooms roses such as David Austin, other old antique garden roses, and floribunda roses require less pruning because their open look is part of their charm. Keep this in mind and prune lightly. Old garden roses that bloom once in the spring should be pruned after flowering.

I got off easy this year as one of my roses was pruned and de-leafed by a deer who got inside the fence one night but the others are getting pruned the right way and at the right time. I know those old leaves will spread fungus spores and possibly infect the new growth so I’ll patiently pluck them off.  If you have a huge climber this might not be possible and spraying with fungicide may be your only option if you’ve had disease problems in the past. Rake up the debris beneath the plant and discard to eliminate overwintering fungus spores. It?s a good idea to spray the bare plant, coating the trunk, branches and twigs and the surrounding soil with a combination organic horticultural oil to smother overwintering insect eggs and a dormant spray like lime-sulfur or copper soap to kill fungus spores. If you usually only have problems with black spot you can use a mixture of 1 teaspoon baking soda with a few drops of light horticultural oil in 1 quart water and spray every 7 to 10 days during the spring.

Pruning intimidates some gardeners but when you understand the reasons for making the cuts pruning becomes less daunting. The reasons to prune are for health, appearance and to control size.

Prune your roses throughout the growing season, too. Deadheading or cutting off spent flowers encourages plants to re-bloom. Every time you cut a rose bloom to bring it indoors or deadhead a fading rose prune the stem down to shape the plant at the same time. Prune to a spot that has at least 5 leaflets. Roses grow from the point where they are cut so consider the overall shape of the plant as you snip.

Don?t worry whether you?re pruning job is perfect. Roses are super forgiving and you can always trim them up again later. Roses are like redwoods -you can?t kill one- they?re the energizer bunnies of the plant world.