I generally go by daylight hours and the corresponding solstices, as that's what my obsessively-high number of seedlings respond to, and as seeing how starting seeds when the hours of daylight are diminishing will be problematic without artificial controls, etc...

"Spring" though seems to be so drastically different depending on the region, though - In Chicago, where I unfortunately have found myself for part of this winter, it does not come until early May, and even then it seems that potential for a snowfall is not 100% out of the question.

Back in beautiful, smoggy oakland, california, however, spring seems to come february 1st, as judging by the buds elongating on my Metasequoias (they will have burst with the first few days of warm, sunny weather following the first week of february) and the flowers on the plum tree in the backyard.

In Chicago, Metasequoias aren't out until late Aprill, so that's a full 1/4 of a year of difference. So, all depends I guess.

I WOULD TEND TO GO BY HEAT ... oops ... and or soil temps ....

ground thaw around 4/1 .. is a good transplant time for me... 6 to 8 weeks of temperate ambient temps.. as the soil increases temps .... great root growing time .... nearly saturated SAND .... a good thing for me

spring is from ground thaw .... around 4/1 until the 70's set in ...

by mid may .. we can plant seeds of tender annuals [veggies] ... since they take about 1 to 2 weeks to sprout ... after which.. all danger of frost is gone 99% of the time ...

by which time .... 6/1 or so.. we are into warm soils ....

by july .... this is when the soil can start drying.. as we can be anywhere from the 70's into the 100's .... yeah will.. a month of 100 degree days possible ... in august ...

this is watering season ... aka drought season .. when babes need supplemental watering ... and where.. perhaps.. the seeds of winter damage is spawned .... warm days.. warm nights ...

then by about mid September .... we start spiraling down into the 70's again ... but as time passes .. we can get into the 50S at night .... which as i understand.. is root growing time in my clime ....

by 10/1 ... its transplant season .. reliably 60's during the day ... 40 to 50's at night... we can sever all roots ... and yet have warm enough soil.. for some regeneration of roots before ground freeze around 1/1 ...

then just misery and disgust from 1/1 until 3/15 or so ....

my point.. it isnt a single factor ... which zone info temps to be.. its not just minimum ambient temp... but a function of air temp.. soil temp.. and moisture .... both air and soil .... and the NORMAL CYCLES of the planet earth .. around her sun ...

BTW ... if i move something 4/1 .. and water it well ... mulch properly .... most likely.. it will not need more water until mid june .... or until my finger says so.. same in october ...

i wonder if this answers your post.. drinking coffee .... losing focus...

ken

You can get seasonal dates from Morocco and Algeria. But I think they belong on the Palms Forum, not the Conifers Forum

;-)

Here in Orlando Florida we do actually have seasons, though they are much less pronounced. Spring for us starts in early February when the deciduous trees start to leaf out. The Taxodiums are really variable in their time frame for leafing out. I have one already leafing out right now, whereas I've seen some in the area wait until mid to late March. Some of our other deciduous trees wait until March to leaf-out also. Summer starts in early to mid May (when average tamps hit mid to upper 80s and we begin to get some 90 degree days). This lasts from then until around October 1, followed by "fall" which lasts until at least mid December. Whether we have a winter or not is debatable. As they say, our 4 seasons are "getting hot, hot, still hot, and pleasant". I have recently been interesting in trying some conifers, and since a nice spruce is out of the question, I would like to try a Wollemi Pine or Torreya.

We definitely have four seasons in our part of California. As a child it always confused me that the weather never followed the exact seasons of the solar calendar...

As with Willfirefight (I like the name "Sparky"), the seasons overlap:

Winter November to February
Spring February to May
Summer May to September
Fall Sept to November

Barbara

North-Central Tenneessee is sandwiched right between zone 6 and zone 7, so we have some pretty wild seasonal fluctuations. But for the most part we have the 4 seasons with about average duration and some overlap:

Winter - November thru February (usually late Nov)
Spring - March thru May
Summer - June thru Sept
Fall - September thru November

In addition we have about 100 different 'Winters', which are used here in the South to describe those frustrating cold spells that interrupt our nice spring thaw (often with disastrous results to the flora). So we have 'Blackberry Winter', 'Dogwood Winter', 'Possum Huntin Winter', 'I Got Out on the Wrong Side of Bed Winter' - you name it, there's a backwoods 'Winter' to describe it! LOL!

K4

Late Feb - early June - Spring (usually hot muggy doesn't get here until Late June). YES, spring is right around the corner.
Mid June - Early Sept - Summer (July and August classified as unbearably hot) This can either be sunny clear and very dry with highs close to 100F or muggy humidy with highs close to 90F. Take your pick! By Sept the humidity usually goes down.
Mid Sept - late Nov - Fall, I usually rake the leaves Thanksgiving weekend. Fall starts off dry in Sept and Oct then rainier in Nov. Fall is a little short but Oct is glorious. Clear, dry, sun with highs around 70-75.
Early Dec - Mid Feb. Winter. Usually Dec is rainy and cool. Then cold and drier until Spring. The coldest weather is around Jan 20. Most of the time the dangerously cold weather is gone by first of Feb.

When we first moved over here,people told us there are only two seasons : winter and summer.We have in the space of 20 years never experienced that.What IS fairly common,however,are seasonal 'come-backs',that is winter coming back end of april,often with disastrous results,or fall/late summer weather coming back after a short cold snap at the beginning of november.In a NORMAL year,the rainy months here are may/june (thunderstorm-type)and october.Last year could be classed as HIGHLY ABNORMAL! T