general seed germination question for the Pros and Experts

If one meets MOST of the requirements indicated for the successful germination of a specific seed, but can't provide the denoted 'temperature' requirement, does this:

- unequivocally doom the seeds?
- not unequivocally doom the seeds but germination is a crapshoot?
- not doom the seeds but germination will take longer?
- introduce any other variables, pro or con?

To be more specific, let's say a seed calls for 'warmth', which in certain instances would be defined as bet. 75/80 degrees F; if the seed sower can only provide 'room temp', which is at its lowest, 60 deg F, and at its highest, 75 deg F, will the batch of seed, placed in a part of the location where they'll be subjected to approx. 70 deg F, be likely to germinate--but at a slower rate--or not at all?

Whoever has some kind of insight into this question, PLEASE ADVISE!

Thanks!

BC,

In the specific case of my seedless triploid watermelon seed, omitting the warmth resulted in zero germination. So, in that one case, there was "unequivocal doom." The next time I try to germinate triploid watermelon seeds, it will be with the help of a heating mat.

For more information on the effect of temperature on germination, see Tom Clothier's article on Germination Temperature:

http://tomclothier.hort.net/page11.html

Tom Clothier's Garden Walk and Talk website is loaded with good information, in case you feel like browsing around.

MM

Hello Maine,

I'm familiar with Tom Clothier's website; you're right, it's a great source of info--and I'll go back to it to see if I missed some vital tidbit that might resolve my current quandary.

About your non-germinated watermelon seed--did you plant them indoors or out--and what time of year? I know it can get pretty chilly out east--particularly the New England area. Is the variety of watermelon seed you tried to germinate considered 'fussy' with regard to its requirements? Also, statistically, how much time do they generally need to germinate? Did your seed bite the dust altogether--getting mushy and fungus-y? How did you decide that they were kaput?

The way my home is--transitionally--set-up, I can offer seeds either 'light' or 'warmth' but not both. This inflexibility will change, but in the meantime I've got some seed-projects going and although they're not entirely light-deprived, they're only receiving 'ambient' as opposed to 'direct' light. In any event, I'll continue to experiment.

Thanks for your feedback on this!

BC,

"About your non-germinated watermelon seed--did you plant them indoors or out--and what time of year?"

When I grow them, I start all of my watermelon seeds early inside under fluorescent lights, about the middle of May, to set them out during the first week of June. The room temperature was maybe 70 degrees, but the temperature under the lights was at least 5 degrees warmer.

My diploid watermelon seeds germinated rather quickly in five days or less. The triploids did nothing and, after about 10 days, I checked a few of the seeds. They appeared to be dead, but not noticeably decayed and they had no noticeable fungus. However, at least some of them came in seed packets treated with Thiram, so you wouldn't expect fungus on them.

I tried about half a dozen different varieties of seedless triploid watermelons and about half a dozen different varieties of diploid (seeded) watermelons. All of the triploids failed and all of the diploids succeeded. By the time the diploids had their second set of true leaves and were looking like they were starting to vine, I gave up on the triploids and removed them from my plant stand.

I have since added heat pads to all three shelves of my seed-starting light stand, and nearly everything germinates significantly faster (and I think better) with bottom heat. Zinnias germinate in as little as two days with bottom heat, while they can take a week or more to germinate without it. As soon as they get their first or second set of true leaves, I move the seedlings to an unheated plant stand equipped with overdriven fluorescent lights to develop them further before setting them out. I am currently setting out some zinnias that are in full bloom.

MM

If you can offer seeds warmth but not light, you might consider placing seed flats in a warm spot until you see germination, and then moving them under lights.

Some seeds -- peppers for example -- will generally germinate fine at "room temperature," but germination will be slower (maybe even 3-4 times as long) than at 78-80 degrees.

Hello Critter-

Your tip about 'warmth' followed by additional 'light' is most encouraging. Does this principle apply in reverse? e.g.: can the seeds that were receiving light rather than warmth, then we switched with the previously warmed ones [assuming the warmed seeds show signs of germination]?

Logically, I should be tailoring my seeding efforts to available space and equipment--but I'm sure many, if not all of the seed/plant aficionados out there can sympathise with someone going overboard due to enthusiasm! If I lived alone, every inch of available space would be consumed; as it is, there's a bit of ongoing territorial sparring between myself and my husband! So, I try to 'time' things right--although some seeds get lucky and some get the shaft [not really, but they more or less have to wait in line!]. A few seeds that require some mild a.m. and afternoon light have lucked-out with the bedroom window sill. I have other seeds and plants poised in a number of 'Rube Goldberg' structural variations.

I actually DO have a heating pad---but I have to provide it with 'real estate', which is tricky. Aside from the virgin heating pad, the best source of additonal warmth is the top of an enclosed 14watt fluorescent bulb on top of an unused 10-gallon fishtank.

Although I'm not, by nature, 'patient', I generate a miraculous store of patience for the process of midwifing seeds. In this instance, with regard to 'who shall receive light, and who shall receive warmth'--I'm concerned primarily about whether or not the seeds will EVENTUALLY sprout if they receive less light [not NO light] or warmth than is ideal.

Any further input on this is welcome!

I'm not sure I understand your question about reversing things... warmth (even without light) will speed germination for many seeds. After germination, light is very important. Inexpensive florescent shop lights (32 or 40 watt bulbs, usually 48 inches long, regular "cool" lights are fine for seedlings) are often an excellent solution... They can be rigged so that they are just an inch or two above the top leaves of the seedlings, and a double tube fixture will provide enough light for two flats (10 x 20 inches) of seedlings.

Some seeds require light in order to germinate (although even a small amount of ambient light may suffice), and other seeds actually germinate best in darkness... see Tom Clothier's site for examples.

There are no rules that apply to every seed. I wish it were that simple! Most (but not all) seeds that germinate best under warm conditions will still germinate under cooler conditions, but it will take longer, and germination rates may be lower. I've read in various places that temperatures over 84 degrees or 86 degrees can kill seeds, although this is clearly not true of all seeds... still, that made me cautious enough to invest in a thermostatic control for my seedling heat mats (which I love).

I'm concerned about the heating pad you mentioned. "Official" seedling heat mats exist, and there are low cost alternatives (heat cables, light boxes, etc) that have been discussed in other threads especially in the propagation forum. However, household heating pads and electric blankets are NOT designed to be used 24/7, nor to be used with anything on top of them (even folding an electric blanket over on itself is hazardous), nor to be used in potentially wet conditions... all those warnings are there for a reason, and the possibility of an electrical fire is just not worth the risk.

Dear Critter-

Not to worry about the 'heating pad'; what I have is a legitimate device designed specifically for germinating seeds---I purchased it from Stokes' Seeds. I may do a lot of things 'by the seat of my pants', but I have Common Sense, and wouldn't do anything such as what you feared I might be doing with an 'ache and pain' type of heating pad, or electric blanket!

Sorry if my question was confusing; but your reply DID answer it! I now have enough input on the 'warmth/light' issue to make more informed decisions on my own.

THANKS!

Good. Sorry about the soapbox -- the heating pad/electric blanket issue is a warning I've added to countless threads. I didn't mean to impugn your common sense, but you'd be surprised how many people just don't pay attention to those warning tags... I think it's partly because everything we purchase now seems to come with a myriad of ridiculous warning tags, and that tends to dilute the impact of the important ones.

Good luck with your current & future seed starting efforts! Hmmm, did I remember to warn you that nurturning little seedlings can be almost addictive? I think I put 22 flats under lights this year... Oh, and check out the wintersowing forum also, for a different approach to the whole warmth/light thing!

Critter-

I did not take the slightest offence at your 'soapboxing', as you put it. Many folks out there are somewhat oblivious to the frequent haplessness of their fellow citizens; I'm glad that you, along with others on this site, Give a Dang!

I'm already addicted, not only to seedsowing, but to rescuing potential plantlets from grapefruits and Manilla mangos---2 of my favourite fruits. I have a beautiful little mango tree flourishing on one of the windowsills; I gave away a couple more. I have a veritable citrus grove: grapefruit, blood orange, meyer lemon, and misc. limes. When I crack open a citrus fruit and there's a 'started' seed, it's hard for me to give it the heave. I have forced myself [for obvious practical reasons] to be inured to the process of culling 'weaklings'---but it's still a bit sad to me. Being sentimental is impractical, and when one considers Darwinian Evolution, it would occur naturally anyway!

On Granville Island, a charming portion of Vancouver, BC--near the downtown, westend area [where I live], there's a little international spice market [in the huge Public Market bldg.] that carries rare fruits and such that are heavily used in culinary efforts. Have you even eaten fresh Tamarind? It's not for everyone, but I developed a hankering for it years ago when I befriended a West Indian coworker who introduce it to me. After one eats the tasty flesh inside the frangible pods, there are several mineral-hard seeds intertwined with this ropey, fibrous netting [that one of my cats loves to play with and chew on].

Recently, I conducted an experiment wherein I prepared one of the tamarind seeds the same way I'd treat a lotus seed, with an intent to germinate it: I abraded part of the seed [I like using emergy boards] until a bit of cream-coloured interior flesh was revealed; then I soaked it for bet. 24-48 hours; THEN, I planted it. I would recommend growing one of these trees to anyone; it's been a few weeks and the seedling is at the stage where it's unfurling beautiful acacia-like leaves. It will probably be years before it produces fruit--assuming it survives--but it's worth growing for the foliage alone, and is a wonder to behold in the process.

I've also grown a Litchi treelet 'from mouth to pot'. Litchi's also have a frangible shell; when one consumes the fruity/perfumey flesh, there's an enormous seed that's good to go pronto---and they grow pretty swiftly!

I'm will to experiment with just about any seeds I can get my hands on--purchased in a packet, or not!

A friend of mine grew dozens of little tamarind trees one year... I'm pretty sure she just used the seeds from a block of the dried tamerind fruit that you can buy at an Indian grocery... she soaked the block to use the pulp in a recipe, then looked at the seeds and said, "Hmmm, I wonder what would happen if...." :-)

They didn't fruit for her, but she only had them (as house plants, in NC) for a year or so before they moved to CA, and I believe she simply gave them away to friends and neighbors before the move.

I've never eaten fresh tamarind, but I do like adding it to curries. I usually buy the paste that comes in little plastic tubs, although I recently picked up a box of "DriTam" pellets that I thought might be less messy (probably less tasty too, LOL). I'd love to find fresh Litchi fruit -- I love the canned ones, and I can only imagine how much more delicate the flavor would be with fresh fruit!