Saving Seeds From Year To Year?

[flowerbug]

How sweet! I love thoughtful neighbors.
Even if the seeds don't grow, it's nice to be thought of.

 

[digitS']

Just for fun, I scattered the arugula and lettuce in areas where I hadn’t planned to grow anything. Let’s see what happens.

How did that work out, Ben E Lou?

Putting seed from several packets into the same seed-starting containers gets me in trouble, every year. Recently, I lined up some tomato seed, using only my "standard" that my seed had better not be over 5 years old and commercial seed could be that old but special positioning would be all that was necessary. In other words, older seeds should be on the outside of the container so that faster germinating seedlings wouldn't be so likely to shade them.

I had some Sun Sugar seed from 2014. Okay, I knew that if the packet says "for 2014," that it is 6 year old seed grown in 2013. What happens? The row of Sungold seedlings emerging about 7 days earlier and nearly smother the Sun Sugar seedlings.

Oh, I think 95 - 100% show up but they are just tiny, tiny things that I have to be soooo careful not to shake up too much as I move the robust Sungolds out to cell packs. I doubt if I did it to the nth degree needed ... but I tried! Still have a few of the 2014 seed. Keep it until 2020? It would require some bother - maybe I'll close my eyes and toss it.

Steve

 

[so lucky]

I had some mixed cherry tomato seeds that I didn't want to put in the garden, so I just tossed them in the empty chicken yard. They grew into huge tangled masses of plants that actually produced few tomatoes. and of inferior quality. Too bad I didn't have any chickens in there to clean it up.

 

[Zeedman]

A little seed science before the growing season gets completely underway.

In one of their quarterly publications, SSE just published the results of a long-term seed longevity testing project. They germination tested about 700 samples total from 30 different crop types - to compare with results obtained from the same samples 10 years prior. The intent was to document the rate of decline, and to compare that to published data. Even if you have never considered freezing seeds, this may still be interesting.

All the seeds tested had been continuously stored at 0 F. degrees (-18 C). The number of years a seed can be stored at those temperatures before the germination rate reaches 50% is termed the P50. These were their results:

Crop type	Initial germ	Final germ	Reduction	Published P50	Calculated P50
Bean	.92	.77	.15	40	33
Beet	.85	.8	.06	40	90
Corn	.87	.77	.1	50	51
Cowpea	.8	.6	.2	45	26
Cucumber	.94	.83	.11	87	43
Eggplant	.85	.59	.26	50	19
Kohlrabi	.97	.92	.05	23	111
Lettuce	.94	.87	.08	23	66
Lima	.93	.76	.18	15	29
Melon	.87	.8	.07	66	73
Okra	.84	.61	.23	20	22
Onion	.88	.7	.18	30	28
Pea	.71	.66	.04	97	111
Pepper	.81	.6	.21	29	24
Radish	.91	.9	.02	120	313
Squash	.92	.8	.12	70	41
Tomato	.97	.89	.08	73	63
Watermelon	.86	.72	.14	68	35

---

The method used to calculate SSE's P50 was not explained. The report did not detail the initial age of the seeds, the conditions under which seeds were germinated (which I assume is part of the P50 standard), or the number of seeds tested.

It does, however, provide a glimpse into potential storage life under ideal conditions. More importantly IMO, it shows the relative rate at which various seeds deteriorate - even under ideal conditions. That info is useful to seed savers, for setting realistic storage expectations... because as the chart shows, frozen seed shouldn't be assumed to live "forever". I was actually surprised that the germination rates were so low for quite a few vegetables, given the long lives often quoted for frozen seed.

The P50 can be used similar to DTM, not for setting absolute storage life under various conditions, but to determine which seeds need to be renewed most often. I've already observed that pepper seed deteriorates in just a few years at room temperature; and this year's germination showed that soybeans (not tested above) also have a short storage life under those conditions - even in sealed packaging.

 

[flowerbug]

A little seed science before the growing season gets completely underway.

In one of their quarterly publications, SSE just published the results of a long-term seed longevity testing project. They germination tested about 700 samples total from 30 different crop types - to compare with results obtained from the same samples 10 years prior. The intent was to document the rate of decline, and to compare that to published data. Even if you have never considered freezing seeds, this may still be interesting.

All the seeds tested had been continuously stored at 0 F. degrees (-18 C). The number of years a seed can be stored at those temperatures before the germination rate reaches 50% is termed the P50. These were their results:

Crop type	Initial germ	Final germ	Reduction	Published P50	Calculated P50
Bean	.92	.77	.15	40	33
Beet	.85	.8	.06	40	90
Corn	.87	.77	.1	50	51
Cowpea	.8	.6	.2	45	26
Cucumber	.94	.83	.11	87	43
Eggplant	.85	.59	.26	50	19
Kohlrabi	.97	.92	.05	23	111
Lettuce	.94	.87	.08	23	66
Lima	.93	.76	.18	15	29
Melon	.87	.8	.07	66	73
Okra	.84	.61	.23	20	22
Onion	.88	.7	.18	30	28
Pea	.71	.66	.04	97	111
Pepper	.81	.6	.21	29	24
Radish	.91	.9	.02	120	313
Squash	.92	.8	.12	70	41
Tomato	.97	.89	.08	73	63
Watermelon	.86	.72	.14	68	35

---

The method used to calculate SSE's P50 was not explained. The report did not detail the initial age of the seeds, the conditions under which seeds were germinated (which I assume is part of the P50 standard), or the number of seeds tested.

It does, however, provide a glimpse into potential storage life under ideal conditions. More importantly IMO, it shows the relative rate at which various seeds deteriorate - even under ideal conditions. That info is useful to seed savers, for setting realistic storage expectations... because as the chart shows, frozen seed shouldn't be assumed to live "forever". I was actually surprised that the germination rates were so low for quite a few vegetables, given the long lives often quoted for frozen seed.

The P50 can be used similar to DTM, not for setting absolute storage life under various conditions, but to determine which seeds need to be renewed most often. I've already observed that pepper seed deteriorates in just a few years at room temperature; and this year's germination showed that soybeans (not tested above) also have a short storage life under those conditions - even in sealed packaging.

i wish they'd put the trailing zeroes in those numbers, it threw me off for a bit thinking that something had gone from 87 to 8... those little decimal points aren't always easily seen by me (sun in my eyes at the moment ).

 

[digitS']

The FDA decision was to use 0°f for home food feezers but I wonder how many of us know what temperature ours is. Most folks may not have given much thought to measuring that and how much difference it makes for seed storage. I imagine that it is significant and yet here I am having never, in long years of gardening, stored seed in a freezer.

An enthusiastic seed catalog reader, it is part of gardening pleasure to try something new. Risk-aversion is something of a burden because I fully recognize the reality of wasting gardening ground, time and energy on a "new" variety that doesn't pan out. Progress in every stage of growing and corner of the garden is what I am striving for.

Once again, I'm babying along seedlings this Spring while seeing cousins of a different variety race ahead. Never having done the research to know - are these seed harvesting, storage, or age differences. I'm surprised if weak sisters ever, really catch up.

Simply seeing very old seed sprout must give the heart A Lift. Imagine if it is our grandparent's or great grandparent's!

Steve

 

[digitS']

@Zeedman , this is probably a good place to ask.

I was recently looking through a thread on another forum. The sub-forum was on winter sowing. I know next to nothing about this subject. It has to do with starting seed in the winter, with minimum protection under a cloche or something like it. Many weeks may be needed before the seed germinates. (It's kinda the opposite of using a heat mat .)

Those gardeners doing winter sowing seem to be enthusiastic about suitable varieties or, maybe, just encouraging others with seed exchanges. @Zeedman is this method of starting seed something that you are experienced with?

Steve

 

[Dahlia]

I've read conflicting information about this. Some sources will say that germination rates and plant health both decrease dramatically if not using seeds from the current year, while others will say that it's worth saving seeds for several years. I'd love to hear the experiences of some folks with more experience than me on this front.

I have been saving my kale seeds and snow pea seeds for about 4 years so far. Every year the veggies are excellent!

 

[R2elk]

@Zeedman , this is probably a good place to ask.

I was recently looking through a thread on another forum. The sub-forum was on winter sowing. I know next to nothing about this subject. It has to do with starting seed in the winter, with minimum protection under a cloche or something like it. Many weeks may be needed before the seed germinates. (It's kinda the opposite of using a heat mat .)

Those gardeners doing winter sowing seem to be enthusiastic about suitable varieties or, maybe, just encouraging others with seed exchanges. @Zeedman is this method of starting seed something that you are experienced with?

Steve

I winter sow my sweet clover seeds. I broadcast them on top of the snow.

 

[heirloomgal]

Does this mean pea seeds can last 111 years with a 50% germination rate if stored at those temp's? If this is true, that would be incredibly good news for pea savers like me. They have the 2nd highest P50 of all listed crops.

Pea

.71

.66

.04

97

111