Encanto Farms Nursery > Categories > Dormancy questions

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rich

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Posts: 110

I understand that most container grown figs require about 100 accumulated hours below 35 degrees. Is this correct 35 degrees? What would be the lowest temp limit?

Does the length of dormancy have any bearing on the time it takes to break dormancy? (Last Spring a couple of 4 month dormant figs took 55 days to leaf out once set outside in early May.)

If one were to keep the garage above 40 degrees (to keep plants from dormancy) all winter long and then allow 1 week (100 hours) of temps below 35 for dormancy in late April, could the plants then be set outside to get a jump on the growing season?

dkirtexas

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Posts: 1,334

THIS IS A PLEA FOR EDUCATION FOR ME

I am not sure where this data comes from.  As I have said in similar threads, I have seen figs in Miami, Fl, The Bahamas, all over the Middle East and they all do okay without the "chill hours".  I have now determined that I do not know anything about this subject and I am now begging for some data on this subject.

Please enlighten me!

BTW - I kept all my figs in a controlled environment all winter, they never went dormant and they all did okay, figs and leaves, and growth

DallasFigs

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Posts: 990

<--- will be watching this thread intently.

OttawanZ5

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Posts: 2,551

Figs are not evergreen so they go through dormancy by dropping leaves. I have read that there is a period over which the plants stay in natural dormancy. After this natural (length of ) period if the ambient are suitable for growth, it will wake up and break the dormancy. If temperatures are low the plants will stay in dormancy until temperature are above a certain temp (probably 45F). This is my understanding as I remember.
The other part, some plants greening up much later. It happens to some of my plants in Zone 5 when stored in uninsulated/nominally heated (above freezing) garage which is sometimes opened for taking garbage to the curb. The delay in greening is most probably due to damage to some of the roots. The delay depend on whether damage was only to the smallest feeder-roots or the intermediate roots connecting feeder roots to the fat roots. Sometimes in sever conditions, some of the intermediate roots can get damaged too. If some roots have survived, it takes time for more roots to develop and eventually the green growth.
This is my understanding if remember correctly. Someone can correct if any statement is not to the point.

Chivas

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Posts: 1,675

http://bluemountainscommunitygardens.org/2013/10/01/chill-hours/

http://fruitsandnuts.ucdavis.edu/Weather_Services/chilling_accumulation_models/Chill_Calculators/

T
hese may be of some use for you

Ruuting

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Posts: 613

From what I've read, chilling requirement for fruit trees is the amount of time the temperature is between 40 and 50 degrees. Anything below or above those temps doesn't count towards the chilling time. This period of time is considered the rest state, and it's the time when fruit buds are prepped for the next fruiting season, by some chemical reactions that I can't begin to understand. After the rest state of chilling, fruit trees enter a quiescent state, where fruit buds are only waiting on temperatures to rise (or days to be long enough) to favor swelling and growth. Maybe it's different with figs, with the old (breba) buds, and the new (main crop) buds, but for other fruit trees, it seems like a fruit tree that requires 100 chill hours...In the northeast U.S. it would complete its rest state by late Winter, and a warm March, followed by a frost, would decimate that season's fruit, which would have been to the quiescent state too early. In the South, a fruit tree that requires 1400 chill hours would not have its fruit buds properly prepped by spring if the temperature never dropped below 50 degrees. Fruit production would be smaller. I'd like to FIG-ure out if there's a way to 'force' main crop or breba figs by controlling temperatures. Imagine the possibilities - Desert King all year 'round!

fignutty

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Posts: 580

The effective chilling temperatures for most fruits are 34-54F. With the optimum at about 40F.

Study figure 4 here:

http://hydrology1.nmsu.edu/nmcrops/Trees/apples/coldhard_dorm/cold-hardiness.htm

Notice there is negative chilling above 60F, 15C, for fruits like apples. But that doesn't apply to figs because they basically need no chilling.

Figs are similar to apples really except they have a smaller chill requirement and a bigger heat requirement to break dormancy.

To wake figs up early they need enough cold to knock the leaves off. In most places that's taken care of in November if not before. Then they need heat to start spring growth. In most places they can be forced to grow in January by moving them into warm days and nights during Dec.

rafaelissimmo

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Posts: 1,473

I found that keeping a potted fig indoors to protect from freezing was the stupidest thing I ever did-for 6 years my Italian fig bore no fruit because it did not receive its chill hours. I prefer let them have a good long sleep in the unheated garage, but this year I will use a greenhouse for late-fruiting varieties such as Smith and Panache, which I will put into greenhouse in early march, about a month ahead of schedule. Just an experiment.