I have been going about an inch deep. Somewhere I read that this was optimum so that there was enough soil to plow through that it loosened the husk. Old wive's tale?
No. Friction. Drape something like a paper towel, wash cloth, etc. over your hand. Cover hand with something that isn't
too heavy; the sheet/blanket/bedspread on your bed might work for this. Move hand in one direction and notice that the paper towel (etc.) tends to stay on your hand. Move it in the opposite direction and notice that the friction of the covers (etc.) acts to remove it. It's the same principle.
Too deep, and the plant uses too much of its finite onboard energy supply. Too shallow, and there isn't enough "travel distance" to help remove the seed case, and that's one of the factors that can end up requiring the gardener to remove it manually.
I'll not hazard a guess as to the actual optimum planting depth. "4x the seed's diameter" seems to be a common recommendation when planting things in general. I don't know whether this is based on any kind of science or merely an easy to remember metric intended to prevent the average gardener from planting tiny seeds way too deep and (relatively) huge seeds way too shallow.
I used to just make a hole and drop the seed in. In recent years, though, I've tried to ensure that I didn't plant the seeds much more than the "4x its diameter" suggestion. Now that I think about it, though... I've occasionally had to remove a seed case from a seedling - and I never used to have to do that. I think I'll go back to just making a hole and dropping the seed in
.
I like it when the root comes out from the top - and immediately makes a u-turn and heads downward. <SHRUGS> But I'm not going to get anal about seed orientation. I've not got the OCD thing, so that would feel too much like work for me. Those who
are so afflicted probably make better gardeners than I do, lol. Plus, I'm pretty "burnt" and never can remember which way the seed has to be for that pattern of initial root growth to occur, and have to look it up every time I decide to worry about it. Once I manage to get something into long-term memory, it tends to stick but, wow, it sure is difficult to get to that point. I don't mean
sometimes, either. I used to do a lot of interior house painting and I'd regularly get lost. Empty house, where I wasn't worried about the homeowner, I'd head to the bathroom and end up in the other end of the house, or to the front door to carry in the rest of the supplies and end up in the kitchen half the time. Occupied house? The guy I painted with always knew when I headed to the bathroom, because I'd have to ask him for directions. Every time. Probably end up with dementia and no one will notice for the first two or three years
. Er... I ramble.
The seeds get wet, but the water slowly receeds, bringing in oxygen behind it. In the soil, there is the added advantage that the direction of the water is downward, enticing the root to follow, and giving the seed something to orient itself on.
Roots grow downward - and stems grow upward - in general, due to gravity. With the former, it's called geotropism; with the latter, it's referred to as negative geotropism. Consider gravity to be the stimulus that provokes the behavior. The auxin that actually causes it is indoleacetic acid. No, I didn't pull that from memory
. Well, not my memory - I have a pretty substantial (and varied) set of bookmarks in the web browser. Here are some of them:
Study of a growing plant's response to changes in the direction of gravity.
www.sciencebuddies.org
Free kindle book and epub digitized and proofread by volunteers.
www.gutenberg.org
On this day 10 years ago, Space Shuttle Discovery was launched to the International Space Station carrying ESA's European Modular Cultivation System – a miniature greenhouse to probe how plants grow in weightlessness.
phys.org
NOTE: Above links not guaranteed to be in agreement with each other (or, for that matter, reality). Nor are they guaranteed to be of use to you. If not, I hope you'll forgive the post.
As a bit of a personal disclaimer, I have (at various times), pre-soaked seeds in tap water, dechlorinated tap water, tap water to which I've added some 3% H
2O
2 (which also dechlorinated the water), tap water after first swirling them around (for 30 seconds and less) in 3% H
2O
2, a very weak solution of Neptune's Harvest Organic Seaweed Plant Fertilizer (0-0-1, from Ascophyllum Nodosum), a very weak solution of Neptune's Harvest Organic Fish & Seaweed Plant Fertilizer (didn't bother to go reread the label), a very weak solution of Olivia's Cloning Solution (didn't bother to reread the label), and a very weak solution of Dragon (brand) Plant Starter with Vitamin B
1 and Chelated Iron (I think it's 3-12-4, but I'm not positive, because it's probably older than half the forum members, from the mid-'80s at a guess, and its label is somewhat faded). Also a weak solution of "something or other from SNS that I do not remember the name of." I couldn't say whether one thing worked significantly better than another. The overall impression I got was that either whichever one(s) I tried at the time worked... or none of them did. I concluded that the important thing was... water. And whether the seeds were actually viable. I suppose that germination/seedling aids are a lot like the gizmos and liquids/powders intended to aid in rooting one's cuttings; they probably do have
some ability to help, on average - but for most people, most of the time, are completely unnecessary. Because, unless we've completely screwed up the species (and we haven't with this one)... if any of that stuff was really required, the species would have died out many thousands of years ago
.
I used to do the dampened paper towel thing, because I was worried about "drowning the seed." But I'm a bit of a klutz and half-blind, too, so I switched to a cup/glass of water. I still worried about "drowning," though. Until (add "forgetful" to everything else) one day, when I remembered that I had chucked a few seeds in "a week or two" previously, ran in to check on them - and found some very tiny seedlings in the water. They'd been like that long enough to have lost much of their green color. I confessed this to Susan (aka SweetSue) as she was the person that gave the seeds to me. She basically just laughed and told me to try growing them because they might still be alive. For some of them, she was correct. So now I don't worry about it, within reason. Relatively fresh seeds that have been stored at cool temperatures seem to work 100% of the time (or very nearly so). Older seeds that I've been given by other people who stored them at room temperature, and that I kept upstairs (where it's miserably hot in the warmer months) have been far more of a crap shoot, even when I sanded them lightly with an emery board or sandpaper in hopes that it would make it easier for moisture to enter the seed case. I think placing those into the refrigerator for a period of time immediately prior to attempting to germinate/sprout them might have helped, but am not sure because my refrigerator quit working shortly after deciding to start trying this.
