germination time, soil temp, longevity of seeds and ph levels for vegetables

majorcatfish

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found this on the hard drive while cleaning it out , figured would share it...some good information.. really like the soil temp chart for direct seeding..






Vegetables ph levels

Asparagus 6.0-8.0
Bean, pole 6.0-7.5
Beet 6.0-7.5
Broccoli 6.0-7.0
Brussels sprout 6.0-7.5
Cabbage 6.0-7.0
Carrot 5.5-7.0
Cauliflower 5.5-7.5
Celery 5.8-7.0
Chive 6.0-7.0
Cucumber 5.5-7.0
Garlic 5.5-8.0
Kale 6.0-7.5
Lettuce 6.0-7.0
Pea, sweet 6.0-7.5
Pepper, sweet 5.5-7.0
Potato 4.8-6.5
Pumpkin 5.5-7.5
Radish 6.0-7.0
Spinach 6.0-7.5
Squash, crookneck 6.0-7.5
Squash, Hubbard 5.5-7.0
Tomato 5.5-7.5


Approximate life expectancy of vegetable seeds stored under favorable conditions.


Vegetable Years
Artichokes 5 years
Arugula 3 years
Beans 3 years
Beets 4 years
Broccoli 3 years
Brussels Sprouts 4 years
Cabbage 4 years
Carrots 3 years
Cauliflower 4 years
Celery/Celeriac 5 years
Chard 4 years
Collards 5 years
Corn 2 years
Cress 5 years
Cucumbers 5 years
Eggplant 4 years
Endive/Escarole 5 years
Fennel 4 years
Kale 4 years
Kohlrabi 4 years
Leeks 1 year
Lettuce 5 years
Melons 5 years
Mustard 4 years
Okra 2 years
Onions 1 year
Peas 3 years
Peppers 2 years
Pumpkins 4 years
Radish 5 years
Rutabagas 4 years
Spinach 2-3 years
Summer Squash 4 years
Tomatoes 4 years
Turnips 5 years
Watermelon 4 years
Winter Squash 4 years
 
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Ridgerunner

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Interesting charts. I've saved a link, it may come in really handy with my move to a totally different growing zone.

Those are only a piece of the puzzle though. If I wait for the optimum soil temperatures for direct seeding for some of the cool weather crops like lettuce or peas it would be too warm to get any kind of production. But that is a different story if you start them indoors.

You can see why the low 6's is generally a good pH for the garden. That covers you for practically everything.
 

Zeedman

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That is the reason I germinate limas in pots, within an 80 F. degree germination chamber (a thermostatically controlled collapsible greenhouse). A major decrease in germination time, compared to what I would expect from direct seeding... and soil conditions here are almost never ideal early in the season.

I question the validity of most seed longevity charts, though. In paper envelopes exposed to ambient conditions, those numbers might be fairly close. But in closed containers stored at controlled temperatures, much longer seed life is possible. Since I grow seed crops in rotation, it is generally at least 5 years before a variety gets renewed, and 7-8 years is fairly common. Germination is generally still good for most beans, tomatoes, eggplant, and squash. Peppers & soybeans drop off a little faster, sometimes 50% germination or less after 5 years. The only variety I've ever lost in less than 5 years of storage was a pepper, and that was seed of questionable maturity.

As a frame of reference, these are the seed ages & germination rates of some of last year's transplants:
Runner bean "Insuk's Wang Kong" 2014 100%
Bitter melon "Thailand" 2014 100%
Squash "Zucchetta Rampicante" 2009 100% (but germination staggered over 14 day period)
Lima "Hopi Pole" 2013 100%
Cucumber "WI 5207" 2015 100%
Yardlong bean "Chinese Long Green" 2013 90%
Pea "Sugar Magnolia" 2015 100%
Okra "Pentagreen" 2015 100%
Soybean "Fledderjohn" 2014 67% (edamame soybeans tend to deteriorate faster)
Soybean "I-309" 2010 80%
Soybean "Mandarin A" 2012 90%

Granted, these were all transplants started indoors; viability & germination may drop off more rapidly when direct seeded than when germinated under controlled conditions. All of these seeds were stored in freezer bags at room temperature, in an air conditioned home; so seed life can potentially extend far beyond the years listed, even without refrigeration.
 

YourRabbitGirl

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found this on the hard drive while cleaning it out , figured would share it...some good information.. really like the soil temp chart for direct seeding..






Vegetables ph levels

Asparagus 6.0-8.0
Bean, pole 6.0-7.5
Beet 6.0-7.5
Broccoli 6.0-7.0
Brussels sprout 6.0-7.5
Cabbage 6.0-7.0
Carrot 5.5-7.0
Cauliflower 5.5-7.5
Celery 5.8-7.0
Chive 6.0-7.0
Cucumber 5.5-7.0
Garlic 5.5-8.0
Kale 6.0-7.5
Lettuce 6.0-7.0
Pea, sweet 6.0-7.5
Pepper, sweet 5.5-7.0
Potato 4.8-6.5
Pumpkin 5.5-7.5
Radish 6.0-7.0
Spinach 6.0-7.5
Squash, crookneck 6.0-7.5
Squash, Hubbard 5.5-7.0
Tomato 5.5-7.5


Approximate life expectancy of vegetable seeds stored under favorable conditions.

Vegetable
Years
Artichokes 5 years
Arugula 3 years
Beans 3 years
Beets 4 years
Broccoli 3 years
Brussels Sprouts 4 years
Cabbage 4 years
Carrots 3 years
Cauliflower 4 years
Celery/Celeriac 5 years
Chard 4 years
Collards 5 years
Corn 2 years
Cress 5 years
Cucumbers 5 years
Eggplant 4 years
Endive/Escarole 5 years
Fennel 4 years
Kale 4 years
Kohlrabi 4 years
Leeks 1 year
Lettuce 5 years
Melons 5 years
Mustard 4 years
Okra 2 years
Onions 1 year
Peas 3 years
Peppers 2 years
Pumpkins 4 years
Radish 5 years
Rutabagas 4 years
Spinach 2-3 years
Summer Squash 4 years
Tomatoes 4 years
Turnips 5 years
Watermelon 4 years
Winter Squash 4 years
That is one pretty in-depth chart you have there, I can't imagine something else as deeper and as detailed as this one. I admire your patience.
 

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