Now that winters nearly over I thought I’d give an update on my outdoor St. Ann Satsuma (now finishing up it’s 2nd winter outside) here in Massachusetts.

Links from last year (2013):
http://citrus.forumup.org/about8225-citrus.html
http://citrus.forumup.org/about7822-citrus.html


Unlike last winter when I did not provide any supplemental heat, this winter I supplied minimal heat to keep the temperature inside the enclosure at or above freezing. The idea behind the extra heating is to overwinter fruit on the tree. Without heating last winter the low temp inside was around 28F. This winter (which was significantly more harsh) the low temp inside the enclosure only dropped to 30.8F.

Here’s a few pictures of the setup (nearly identical to last year):


The Early St. Ann:


The Gold Nugget (planted last spring):


The fruit on the Early St. Ann were ready in Early Nov. and the fruit on the Gold Nugget sweetened up in early Feb. I still have 5-6 fruit on the Satsuma and 3 on the Gold Nugget. The overall quality on both is still pretty good (last tasted in early March). If kept cool, it is surprising how long the fruit quality holds for the Satsuma.


In November, December, and January, the heater was set to keep the inside temp above 38F (3C). In February the heat was turned down to keep the temperature from dropping more than one degree F below freezing. From March 1 to March 10 the heat was raised to keep the temp above 38F (3C). On March 10 the heating was switched from the aquarium heater to a small electric heater and the thermostat was adjusted to keep the temperature between 55 (13C) and 65F (18C).

November:
Nov. 1 2013 enclosure assembled
Nov. 4 2013 first frost
Nov. 30 low outside temp for the month 18F (-8C)
Monthly Average temperature inside the enclosure 50.8F (10C)

December
Dec. 17 low outside temp for the month 7F (-14C)
Dec. 17 low inside temp for the month 38F (3C)
Days where the outside temp did not reach freezing: 8
Monthly average temperature inside the enclosure 45.0 F (7C)

January:
Jan. 3 and 4 low outside temp of 1F (-17C) on both days
Jan 8 low inside temp for the month 37.0F (3C)
Days where the outside temp did not reach freezing: 15
Days with a low outside temp of 5F (-15C) or below: 3
Days with a low outside temp of 10F (-12C) or below: 10
Monthly average temperature inside the enclosure: 42.9F (6C)

February:
Feb. 12 low outside temp for the month 6F (-14C)
Feb. 12 low inside temp for the month 30.8F (-1C)
Days where the outside temp did not reach freezing: 12 (8 of these days were consecutive)
Monthly average temperature inside the enclosure: 35.2F (2C)


March 1-21:
March 4 low outside temp for the month 9F (-13C)
March 1 low inside temp for the month 35.6F (2C)
Days where the outside temp did not reach freezing: 5
Average temp (March 1-21) inside the enclosure: 51.5F (11C)
Average temp (March 10-21) inside the enclosure: 58.1F (14.5C)


Here are the monthly temperature graphs:

Key (temps in deg. F):
Green: 4 inch (10cm) depth daily low soil temperature
Blue: inside daily low air temperature
Orange: outside daily low air temperature

November


December


January


February


March (1-17)

you got nasty climate for the latitude you live on, but still enough good weather for satsumas to get ready until november.

Hi Scott

your citrus look great considering how much cold you got this winter. That early St Ann appears to be a winner in our climate since the fruit ripen in November.

You'll have to create some PT x St. Ann and St. Ann x PT hybrids for testing. It would be great to get a citrus hybrid which will survive up here with minimal protection (and be somewhat edible)......Citrumelo is not hardy enough.

Adriano, my climate is actually pretty good for the Northeast US. Some locations only 40 miles or so further inland from my house got down to -15F (-26C) this winter! However, the same latitude in Europe is obviously much warmer...

Tim, St. Ann X PT might be interesting. Not sure PT X St. Ann would work, as I haven't seen much if any pollen on the St. Ann. Also, these crosses might not be any more hardy than the PT X Changsha hybrids... I would love to find out how hardy the Fast PT is and to see if it can pass along it's precocious flowering to Fast PT hybrids.


...just checked up on my St. Ann and it has now broken dormancy! Looks like turning up the heat for the past ~2 weeks has woken it up. Last year it didn't break dormancy until April 17.

We hit -17F at my house up here in Maine this year Scott...it's been a few years since we've been that cold.

Brrrr...-17F this winter! The record low for Boston is -18F way back in 1934 and hasn't been anywhere near the record for decades.

we got to -15 f this winter....
the trees look great

Thanks Frank,
It's crazy how just a few miles can make such a big difference in temperature around here. I was really surprised we didn't get below 0F at my house this winter.

hi
did you pick your fruit? If it is like mine they are starting to dry out

I've picked most of the fruit. There's still 4 or 5 on the satsuma and 3 on the Gold Nugget. I had a satsuma a few days ago and it still tasted fine. The humidity in my enclosure was between 75 and 90% for most of the winter... maybe this helped with keeping them from drying out.