Florida Fruit Geek

Mulberries are a great fruit tree for Florida (and just about everywhere else). But a major challenge in growing them in North and Central Florida is that some varieties get fooled by warm spells during winter into thinking that spring as arrived, and they break dormancy too early.

As long as a mulberry tree is fully dormant, with its buds hardened off, it can usually handle freezing temperatures. But once it breaks dormancy and starts pushing new growth, the tree’s sap is flowing, and if a hard freeze should strike after that point, cold temperatures can kill the whole tree.

So it’s important in North and Central Florida to choose mulberry varieties which sleep late, until danger of hard freezes is over.

This winter had warm weather from about Christmas to the middle of January, which provided an opportunity to assess which mulberry cultivars stayed dormant, and which got fooled by the weeks of warm temperatures and had already broken dormancy by the middle of January.

I compiled my own list of which mulberry varieties were and were not staying dormant at my location in Citra, Florida (between Ocala and Gainesville). I also checked with Josh Jamison of the Heart Institute in Lake Wales, who has a much larger variety collection, and he gave me a similar list for his mulberry varieties.

Here is my list of mulberry varieties breaking dormancy in Citra, Florida. I compiled this list on Jan 13, 2020, and I checked again at the time of this writing, Jan 26, at which point no additional varieties had broken dormancy.

Still dormant:
-‘Green-White’ (still has leaves, buds dormant)
-‘Himalayan’ (still has leaves, buds dormant)
-‘Cooke Select Pakistan’ (still has leaves, buds dormant)
-‘Sixth Street’ (leafless)
-‘Illinois Everbearing’ (leafless)

Dormancy broken:
-‘Cedar Key’
-‘Dwarf Everbearing’
-‘Bryce’s World’s Best’
-‘Mustang Thai’
-‘Edible Leaf’/’ECHO Everbearing’

Here’s Josh Jamison’s report from Jan 18, 2020, in Lake Wales. I’ve broken it into three groups, varieties which were fully dormant, ones early stages of breaking dormancy or partially breaking, and ones fully into active growth.

-‘Sixth Street’ – dormant
-‘White Pakistan’/’Green’ – dormant
-‘Ranger Kens’ – dormant
-‘Valdosta’ – dormant
-‘Tehama’ – dormant

-‘Hunter’ – early stages of breaking
-‘Estero Giant’ – 95 percent dormant
-‘Firk Giant’ – early stages of breaking
-‘Echo White’ – early stages of breaking
-‘Tice’ – a few buds breaking
-‘Shangri La’ – first stages of breaking
-‘Tampa Pink’ in greenhouse – just breaking bud
-Old tree at HEART (probably with rubra genes) – dormant with a couple odd buds breaking

-‘Dwarf Everbearing’ (probably, emerged from rootstock) – well into growth
-‘Worlds Best’ – well into fruit formation, first to break bud
-‘Tigrinum’ – into active growth
-‘Pakistan’ – into active growth
-‘Thai dwarf’ – into active growth and fruit set
-‘Edible Leaf’/’ECHO Everbearing’ – active growth and fruit set
-‘Himalayan’ in greenhouse – never went dormant
-‘Skinner’ in greenhouse – never went dormant
-‘Mustang Thai’ in greenhouse – active growth and fruit

Josh’s ‘White Pakistan’/’Green’ is probably the same one I have as ‘Green White’. His ‘Worlds Best’ is the same one that I am calling ‘Bryce’s World’s Best’.

If a hard freeze strikes during the remainder of this winter, any of the varieties in active growth will probably get substantial damage unless we protect them with blankets, heaters, etc. But if the rest of this winter does not bring any extreme cold, we should get to sample fruit from most or all the varieties on all these lists in the coming months.

We’ll continue to take notes on bud break of our mulberry variety collections during the rest of this winter and during future years, to get a fuller picture of how consistant the characteristic of early bud-break is in years with variable weather conditions. But for now this list should be helpful for anyone choosing mulberry varieties for North and Central Florida – it’s safest to choose ones which appeared on the fully dormant section of these lists.

In South Florida, where freezing temperatures are much less of a concern, you can choose any of these varieties listed on this page.

#Moraceae #mulberry #winter #weather