Apples without sufficent chilling

[fruitnut]

We’re told apples grow and fruit anywhere chilling or not. But it’s a bit discouraging here and we have all winter with nights below 45F. Mostly thou it’s too cold, below 32, or too warm, above 60F. Now here we are facing a week of 100F, already done with apricot harvest, and my trees look like this. I have watered and fertilized.

My second leaf Crunch a bunch or whatever it’s called. I can see this will be a 4-6 ft tall tree if I’m lucky.

Goldrush on MM106 6 yrs and 5ft tall with mostly bare wood.

Then we have Goldrush on 111 at 6 yrs. Notice no weeds or nearby trees for competition and this is all I have on 111. Pathetic.

Ashmead’s Kernel grafted onto the above tree. Not one blossom in 6 yrs and not a single leaf yet.

Gingergold about 12 yrs. I don’t know if this picture really indicates how poorly leafed out and pathetic this tree looks.

My best looking apple a Golden D. Poorest crop ever and I really have watered and fertilized. It just doesn’t look like it.

[Z9gardener]

Thanks for sharing your experience.

[InfiniteFruit]

Hi Fruitnut,

Thanks for sharing. Would you consider to try these apple trees in your controlled environment?

[fruitnut]

I’ve tried apples in the greenhouse. They did OK but the fruit was not great. At least they grew.

The last few yrs the chilling outside has been nearly zero as far as the apples go.

[applenut]

Fruitnut - you have something else going on there besides lack of chill. The lack of vigor is what concerns me. In the photo below these 4-year old M111 trees are in Irvine in Orange County by the Great Park for those who know the area, about 5-7 miles from the beach. They fruit heavily. Those are avocado trees in the background.

This is an M111 rootstock nursery in Tanzania in East Africa showing one season’s growth

And a 600-tree orchard in Uganda, Dorsett Golden in the foreground; they picked 7,000 apples this season from it.

I’d suspect root problems, possibly root rot?

[fruitnut]

It’s not root rot. Possibly weak soil. However other trees that don’t need much chilling grow normally. I had apricots in the same enclosure that were overly vigorous. My neighbor right over the fence has an apricot that is huge after ~4 yrs. His apples look like mine. His peaches, pears, and figs are vigorous.

I’ve grown apples in Amarillo which has about 3x the chilling as here. Apples there had good vigor but it was a stronger soil.

[bleedingdirt]

I have a 4 in 1 apple tree on M111 which grows a bit once during spring and then nothing. It’s in its 5th year and is less then 6 feet tall after I tried bending branches instead of pruning. The trunk has quite a few burr knots but no woolly aphids.

I’m curious to know what might the reason be for your trees’ lack of vigor.

[wildscaper]

Steve your apple experience looks like mine in Austin. No vigor, blind wood everywere and nooooo fruit. Had trees for years too. Her in Dallas it’s a little better but still very little blooms or fruit. Again my trees are old. I don’t know why we don’t get the same results they see in Africa or Cali but we sure don’t.

Drew

[fruitnut]

@bleedingdirt

I’m curious to know what might the reason be for your trees’ lack of vigor.

I think at least part of it is lack of chilling. Maybe we need more vigorous rootstocks than 111. We might need seedling.

Another thought might be woolly apple aphids on the roots. I know they are on the roots but don’t know if that’s the cause.

@wildscaper

I don’t know why we don’t get the same results they see in Africa or Cali but we sure don’t.

Our winters are pretty weird. Here it’s either too warm or too cold for chilling. Our winter this yr consisted of an average weekly high of 76F and a low of 20F. Neither CA nor Africa has winters like that.

Woolly aphids on the roots or inadequate rootstock could account for the lack of vigor. But it’s lack of chilling that accounts for the blind wood, no leaves until summer, and blooming that can last three months on some varieties.

[applenut]

We get all those signs of lack of chill symptoms, but the trees eventually perk up and put out new growth and are full by the end of the season (and then take forever to go dormant). Usually if the tree is stunted like that it is from soggy soil or sunburn/borers. M111 is supposedly WAA resistant, but you might take the weakest one and dig it up to do an autopsy on the roots to see if there’s anything abnormal.

They do dig huge planting holes for tree planting in Africa to break up the clay, typically 4x4x2’ deep. I think this is the best thing they do to encourage vigor.

[castanea]

I don’t know why you think the problem is lack of chill hours. The primary problem associated with lack of chill hours is lack of flowering, not stunted growth. In fact apple trees that get inadequate chilling to flower sometimes compensate by putting on more growth. In some years I get very few chill hours (California zone 9) but all of my older apple trees flower no matter how many chill hours I get. I’m guessing you have some kind of soil or root problem.

[fruitnut]

@applenut

They do dig huge planting holes for tree planting in Africa to break up the clay, typically 4x4x2’ deep. I think this is the best thing they do to encourage vigor.

I don’t have clay soil. It’s a friable light clay loam. Water intake rate is several inches per hr as long as you apply it. The nitrogen does leach right thru with the water and water holding capacity is only moderate but it’s a good soil for fruit trees. Nearly ideal in fact.

@castanea

I’m guessing you have some kind of soil or root problem.

It’s not a soil problem but I already mentioned possible woolly aphids.

I’ve grown apples for 50 yrs in areas with low, medium, and high chilling. I think I know what lack of chilling looks like in apples.

[castanea]

There are hundreds of varieties of apples. They all react somewhat differently to environmental factors and soil factors. What I am curious about is not how much experience you have growing apple trees, but how much you have growing these specific varieties in different climates with different chill hours. In short I’m just wondering specifically why you think this is a chill hour problem. Where are you growing these?

[fruitnut]

@castanea

In short I’m just wondering specifically why you think this is a chill hour problem. Where are you growing these?

I’m growing these in southwest Texas. I’ve also had apple orchards in far north Texas, Amarillo, near Fresno CA, and in northern IL.

It’s at least partly a lack of chilling because the symptoms are those of a lack of chilling. Applenut sees the same thing.

@applenut

We get all those signs of lack of chill symptom

[wildscaper]

Agree it’s lack of chilling. Also agree our winters are weird! I grew Anna and it leaved out fine and grew like a weed on m111. It just bloomed too early most years. I have tried many rootstocks and they produced similar results. In Dallas I am using g16 and the trees are growing very fine. Very healthy. The just produce very few flowers. Like next to nothing. One good crop in eight seasons. Dunno.

[Bhawkins]

Scaper, I’ll have to show you my trees sometime. About 15 varieties in 3rd leaf. I trimmed them at 6 ft tall last winter trying to keep them under control. 15-20 apples per tree this year Mainly m111, some m7, g16, g202. Had to add phosphorous and nitrogen to the soil. I bend some, but not all limbs down. Trees are mostly grown in mulched rows, 3 ft wide.

[JamesN]

Fruit trees decide seasons for dormancy based on two things:
-light
-temperature

We use concepts to understand this and study it:
-photoperiodicity
-winter chill

A plant would probably want to rely on photoperiod, but the problem is there are identical photoperiods at opposite seasons. In the summer we have 14 hours of light and in the winter, 10 hours. But in the fall and spring both it is 12 hours at the respective equinoxes. It is critical that the tree differentiate these. But how?

The photoperiod is the same
The temperature is the same

Maybe it has something to do with the direction of the change?

Coming after a warm season, dropping temperatures during the equal photoperiods (12 hours light, 12 hours dark) trigger dormancy.
Coming after a cool season, rising temperatures during equal photoperiods trigger bloom and bud break.

This means that if the temperatures are erratic, then the tree gets confused. This is analogous to a “signal to noise” problem.

This may be why fruitnut has problems in Texas. The signal is strong but so too is the noise.

From a scientific article I found online:
“Heide and Prestrud (2005) demonstrate that low temperature consistently induces growth cessation and dormancy induction in apple, regardless of photoperiodic conditions.”

Fruitnut, the easiest apples for me here were Braeburn and Anna. You might want to experiment with those? Braeburn fruits as many as 3 times a year for me. At least that tells me that it likes to break dormancy.

Possibility #2: Temperature swings between day and night? Orange county probably has 20 degree swings, even in the winter. Texas might have 60 degree swings? That too may confuse the trees.

If you wanted to pursue #2 then look into apple trees that do well in Arizona.

[fruitnut]

@JamesN

Fruitnut, the only apple trees to do well for me here were Braeburn and Anna

I’ve grown Braeburn in Amarillo, not here. It didn’t do well in Amarillo. It seemed sensitive to summer heat but grew OK. Anna is a complete no go here. We have way too many freezes and it blooms way too early. Temperature noise, that’s a good term, and we have plenty.

[applenut]

The orchard in Uganda is right on the equator and gets 12 hours of daylight pretty much all year; not much temperature swing also, and zero chilling hours. They strip the leaves manually, which tells the tree it’s gone through winter, and since the days are long and it’s 80 degrees, thinks it’s spring and we’d better get on with it and blossoms in about 6-8 weeks.

[InfiniteFruit]

@fruitnut

I think at least part of it is lack of chilling. Maybe we need more vigorous rootstocks than 111. We might need seedling.

Another thought might be woolly apple aphids on the roots. I know they are on the roots but don’t know if that’s the cause.

Question: Isn’t M.111 woolly apple aphid resistant. I remember reading somewhere Malling rootstock bred specifically for woolly apple aphid resistance?