We do not recommend using home remedies to treat pest, disease, or weed problems as the ingredients are at best ineffective or at worst harmful to desirable plants (and possibly the environment as well, such as beneficial soil microbes and beneficial insects). Sodium salt should never be used in the garden as it is toxic to plants - good for weed control perhaps but not helpful when intentional plantings are going into the same area. Plus, you do not want it leeching sodium into nearby plantings with rainfall. Household vinegar is not strong enough to be an effective herbicide, and the horticultural-strength vinegar labeled for use as an herbicide is quite caustic and caution needs to be taken in its application to protect skin and eyes from exposure. It can burn-off top growth but will not necessarily kill roots on perennial weeds.

The more practical approach may be to either have the bricks re-laid into a much tighter configuration so weeds cannot get a foothold, or to continue physical weed removal and/or flame weeding. There are tools meant to scrape weeds out of thin paver cracks which might help alleviate hand strain. For flaming, there are small portable torch-like wands attached to a propane tank that are used to burn-off weed top growth, which if there are no fire hazards in the immediate area (such as wooden bed boards, wooden siding, or pine-needle mulch) may be the solution with the least detrimental side effects. This will have limited impact on perennial weeds, however, which would need have their roots controlled either by being pulled up or via treatment with a systemic herbicide (which won't be organic).

Moss as a gap-filler is a solution if the patio is shaded during the hot hours of the day and stays relatively moist; it does not prosper in hot sun and drying conditions. When it appears in lawns, for instance, it favors shady areas that stay damp and have compacted (poorly-drained, which retains water) and acidic soils.

There is a moss-like perennial called Irish Moss or Scotch Moss (a misnomer as they are not true mosses) that could work as a substitute in sunny, drier spots. There are two varieties, the straight species Irish Moss (Sagina subulata) which is deep green and the other, Scotch Moss, which is a more golden cultivar called Sagina subulata 'Aurea'. The only issue here is that the size of the potted plants sold is larger than you will probably be able to fit in between the bricks (depending on your gap size), and splitting it into smaller pieces may result in the loss of some due to root trauma and transplant shock. If you can find seed for this plant, that would be simpler and probably be a more successful way of establishing it there.

If moss is better suited, you can collect some from elsewhere on your property (if you have it anywhere), dry it out, crush/rub it into a powder, and "sow" it into the cracks; spores and fragments of the moss will germinate/re-animate with consistent moisture and gradually colonize the gaps. Alternately, you could try breaking the moss pillows into smaller clumps to wedge into the gaps and see if they take. Moss growth is slow, but the plants have no true roots, so shock from the move will be less likely if they can be prevented from drying out.

Miri

Thank you for your response.
The brick area is not near other plantings and I have been extremely careful with application of the home remedies. I may try seeding with Irish Moss.

You're welcome.