Seed Today, Sinse Tomorrow
I believe most hobby growers like to make some extra seeds every once in a while. Perhaps you want to cross a couple of strains and make a hybrid, or maybe you just want to share some genetics with your fellow growers. But many times, small-scale, hobby growers don't have the extra space to create a separate area for breeding. These growers might not even have a spare room or closet where they can stash males until the plants drop some pollen. And no one wants to risk leaving them in the same room as the ladies, lest some stray pollen gets loose ands ruins the whole grow! Consequently, many home-growers don't have the opportunity to produce seeds without great risk to their sinse crop.
However, for the desperately cramped seed-fancier, there is a compromise method that works well if you're careful. That is placing a ready-to-drop-pollen male in the flowering box, at the BEGINNING of 12/12, alongside all the young female plants. The idea is to pollinate the females while they have only their preflowers, then destroy the remaining pollen. By pollinating only the preflowers, before the real "nugs" form, you will harvest enough seed for personal use while keeping the main crop seedless.

Keeping your male donors alive
Timing is the key to this procedure. Ideally, the male plant should be ready to dehisce (release pollen from flowers) as soon as the females are put into 12/12. This means the selected male clone should get a head start of anywhere from one to three weeks on the females. This can be achieved by creating a separate 12/12 box. And since it's for a single plant, you can throw something together with a cardboard box, an incandescent light and a timer. Perfect conditions are not necessary.

Fertility Dance

After your male has plenty of ripe flowers and is starting to drop pollen (one to two weeks, typically), it's time for the intended seed mothers to go into 12/12. Hopefully they are clones from mature moms, and have plenty of female preflowers showing white hairs (pistils) at their nodes. The pollen-dropping male goes in there with them for a multi-day "Love-In." During the few days that the male is in there, he should pollinate all of the preflowers. You can help make sure the pollen is well-distributed among the female plants by moving him around a bit and introducing him to the ladies. Having a fan on inside the grow area won't hurt either.

Different strains have differing amounts of preflowers. Some will be so profuse that you will only need to treat one plant. With plants that preflower only lightly, it may be necessary to delay the introduction of the male until after one week of 12/12. I would NOT try this later than one week into 12/12 if you want something you can call "sinsemilla."

Cleaning Up After the Party
The next step is to remove the male (make some Bhang!) and hose the grow down with a pump-sprayer. Also, make sure all your fans are turned off while doing this. No sense in risking any more pollen possibly getting blown about. Spraying the area down will give the plants a thorough foliar bath, soak the soil and moisten all the surfaces where the pollen might have landed. You need not go crazy while doing this and treat your grow area like it was on fire. A good thorough spraying will get rid of any un-wanted pollen. And a couple of repetitions of this wetting treatment for a few days afterwards, with its resulting high humidity levels, should certainly render all of the remaining pollen inviable. Stray pollen loose in the garden is a risk using this method, but not much of one if things are done right.

Here's a pic of a girl subjected to this treatment

This plant has been in 12/12 for 17 days. You can see that the pistils on the preflowers have retracted inside the swollen calyxes, a sign they are forming seeds, while the new pistils are all white, un-pollinated, sinsemilla. With the seeds forming at the nodes, I can see them clearly so they're easy to find, and I can harvest them before the buds finish, because they'll be completely mature by the fifth week of flowering, a full two weeks before the buds are ready.

Seeds only need about four weeks to mature, but additional time on the plant will not harm them. Care should be taken during harvesting to assure that seeds aren't lost due to dropping from the plants during handling or drying. Handling the plants gently is the best way to assure the seeds end up where you want them.

Eggs in the Nest

The Ladies have had two foliar treatments since I removed the male. They'll receive another this week. All remaining pollen can safely be assumed to have been destroyed by the spray-downs, though I do expect to find a seed or two in the bud. In past trials, this method has produced on the order of a couple dozen seeds per plant, give or take a few.

Mature seed will be typically be dry and unlikely to rot, but care should be taken when storing the fresh-harvested seeds. adding a silica gel dessicant to the storage jar for a day or two will absorb any residual moisture without drying the seeds completely (do not leave the dessicant in there for more than a few days). The overall seed yield is low, but you can expect to harvest more than enough to share with a few friends and even set a few aside for a rainy day.

Written by 180. He hopes you're well aware that he is a cosmonaut.