Nursery tree leafing out 2/21/2017
Young pecan tree in orchard leafing out 2/21/2017
We haven’t had much of a winter this year. We’ve only had 4 days where temperatures dipped below freezing in Tifton and the average temperature since November has been 57 degrees as opposed to 55 degrees last winter. We’ve also accumulated only 368 chill hours as opposed to the 559 chill hours we had by this time last year.
For many fruit trees, once buds have entered dormancy, they will be tolerant to temperatures below freezing and will not grow in response to mid-winter warm spells. These buds remain dormant until they have accumulated sufficient chilling units (CU) of cold weather. When enough chilling accumulates, the buds are ready to grow in response to warm temperatures. As long as there have been enough CUs the flower and leaf buds develop normally. If the buds do not receive sufficient chilling temperatures during winter to completely release dormancy, trees will develop various physiological symptoms associated with insufficient chilling.
Its really not clear how many chill hours pecans need, probably because there is so much variation from one variety to the next. It is reported that 300 -500 chill hours are required for Desirable, Mahan, Success, and Schley, while Stuart reportedly requires from 600-1000 (I think that’s a little high, myself). Interestingly, Terminal buds have lower chill requirements than lateral buds. So, after a cold winter you may have heavier crop loads because more lateral buds flower and get pollinated at the right time.
In general, pecans don’t need a lot of chill hours. At the southern end of its range in Mexico, you can have trees that receive less than 100 chill hours, which still produce nuts. The actual chilling requirement for pecans also varies with fall temperatures. If trees are exposed to cooler fall temps (less than 34 degrees F) the intensity of the bud’s rest is greater and the number of chill hours required for budbreak increases. But, the colder the winter, the fewer the heat units in spring required to start budbreak. Heat units in spring strongly influence budbreak and drive the progression of the crop’s maturity. So, with a cold winter and warm spring you can actually get a pretty early budbreak.
We had a warm fall, therefore the intensity of the bud’s rest is weak and the number of winter chill hours required for budbreak will be lower. Indeed if you look around at the edges of fields and in the woods you will see red maples, red buds, and oaks budding out. Azaleas are blooming in the yards. And yes, some pecans are even budding out already as you can see from the pictures above. Unless we have a cool spell to slow things down I expect to see a lot of buds breaking within 2 weeks. What will this mean for the crop?
Well, the main thing is we have to hope and pray for a warm spring with no late freeze. Any late freeze down into the 20’s for any significant length of timeafter the shoots begin expanding, putting on catkins and female flowers will cause serious problems. The tissue would be burnt off by the freeze. The trees would shoot back out, and grow. We would lose that flower crop and some varieties would try to put on more flowers but most of those secondary flowers eitherwouldn’t develop into nuts or the nuts would be of very poor quality (because pollinationwould beoff).
Beyond a late freeze, the most likely problem will be poor pollination. Because budbreak tends to be so sporadic, staggered, and non-uniform when you have low chill hours, the synchronization of female flowers with male flowers from the pollinators is usually off, leading to poor nut set and poor quality. The more cold snaps we have from here on out, the more non-uniform budbreak and flower development will be. So, from this point on we need it to stay warm.
Lenny Wells
I am a Professor of Horticulture and Extension Horticulture Specialist for pecans at the University of Georgia. My research and extension programs focus on practical cultural management strategies that help to enhance the economic and environmental sustainability of pecan production in Georgia.
FAQs
You want a richer flavored pecan? This is typically due to a very high oil content – Elliott, Lipan or a seedling (native) pecan may be best for you.
Do pecan trees need to be watered in the winter? ›
As long as there leaves on the tree, some water is needed. The fall is also a good time to apply an application of phosphorous. Phosphorous takes time to mineralize into a usable form and the winter is a good time to do that. Because you have cut back on your watering, it won't be as likely to leach past the root zone.
Why are pecans so expensive this year? ›
Prices for most varieties are $1 to $1.50 per pound higher than normal for a crop like this year’s. Demand for pecans has increased in recent years, driven by China’s newfound taste for the nut. China purchased 88 million pounds of pecans last year. The U.S. produced 290 million pounds last year.
Can pecan trees survive a hard freeze? ›
A quick dip below freezing lasting an hour or so may not cause much noticeable damage but this long duration freeze was a killing freeze. The week following showed a complete kill of all new growth and swelling buds on our Pecan trees.
Which state has the best tasting pecans? ›
San Saba Pecans set the standard. Regardless of the form you want your pecan to be in, San Saba, Texas is the perfect place to go in order to get quality pecans. Visit San Saba, Texas and enjoy the best pecan ever!
Why do some pecans taste so bad? ›
Store pecans in cool, dry places away from heat: Because pecans contain such a high amount of healthy, plant-based oils, they are prone to going rancid if they spend too long in warm temperatures.
What fertilizer for pecan trees? ›
The use of a balanced fertilizer (13-13-13) or (8-8-8) as the main nitrogen source can correct phosphorous and potassium deficien- cies indicated by soil test. Annual fertilization is the most practical and effective tool available to the homeowner for improving pecan production.
At what age do pecan trees bear fruit? ›
Maturity Rate
On their way to maturity, the trees undergo drastic vegetative growth to develop a robust root system, grow taller, and produce branches. While many fruit trees begin bearing fruit within the first 1-5 years after planting, pecan trees can take anywhere from 2-10 years.
Do pecan trees like sun or shade? ›
Light. While pecans can handle some shade, they will grow best in full sun (8+ hours per day). Avoid planting large-growing trees in close proximity to provide ample space for canopy growth and root expansion.
Who is the biggest consumer of pecans? ›
A. The report identifies North America, particularly the United States, as the largest consumer and producer of pecan nuts. Other significant markets include Mexico, China, and some European countries.
The trees are still standing today! It wasn't until the late 1800s that farmers began cultivating pecans in orchards. Georgia is the nation's largest supplier of pecans, accounting for about a third of all U.S. pecan production.
What is the most expensive nut in the world? ›
Macademia nuts, that are said to be world's most expensive nuts come with an array of benefits. Renowned Nutritionist Kavita Devgan elaborates on the health benefits of macadamia nuts, shedding light on their potential to enhance our vitality and contribute to a balanced lifestyle.
What is the lifespan of a pecan tree? ›
Pecan trees typically grow 75-100 feet tall with a large, distinctively wide spreading crown (canopy). The lifespan of these behemoths can be up to 300 years! The Carya genus includes nearly 20 species. Most are native to North America, including all of those in the Arboretum's living collections.
How many years do pecans last? ›
Keeping Pecans Fresh
| Temperature | In-Shell Pecans | Shelled Pecans |
|---|
| 70 degrees (pantry) | 4 months | 3 months |
| 40 degrees Fahrenheit (refrigerator) | 9 - 18 months | 6 months |
| 32 degrees Fahrenheit or 0 degrees Celsius (freezer) | 2 years | 2 years |
Poor Soil Drainage
Good root growth occurs when the soil is 50 percent particles, 25 percent air and 25 percent water. When the pecan soil is dry the tree will survive by shedding the crop and making very little growth; however, when the soil is too wet, the tree roots will die and this can result in tree death.
What are the sweetest pecans? ›
While thin or "paper-shelled" pecans are easy enough to crack with your bare hand, hard-shelled varieties like the Stuart can have a "discernibly sweeter taste," according to Nuts.com.
What is the difference between Type 1 and Type 2 pecans? ›
To make things a little more confusing, pecan trees come in type 1 and type 2 varieties, where their pollinating and receptivity are reversed from one another. Type 1 trees produce pollen and then have receptive female flowers. Type 2 trees are going to have receptive flowers first and then produce pollen.
Do all pecans taste the same? ›
Even though there are over 1000 named varieties of pecans, each one, has its own taste and characteristics that make it special.
What type is desirable pecan? ›
'Desirable' is supposedly one of the first pecan cultivars developed from a controlled cross. The cross was made in the early 1900's by Carl F. Forkert from Ocean Springs, Jackson County, Miss. The parentage is unknown but may be 'Success' x 'Jewett'.
