How To Harvest and Preserve Basil For Up To 6 Months! To preserve Basil in salt, simply layer sea salt in a jar, and add basil leaves. Keep the salt jars in the freezer and use the basil within six months. You can still use the salt after your done.
Good ideas from Kaylynskitchen - How to Freeze Fresh Basil; I've been using this method for years and years now and I love using the frozen basil for a burst of flavor in winter soups or stews. [from Kalyn's Kitchen]
Preserve hard herbs by freezing in oil! "Given this use, the oil-and-freezer method of preservation works best with the tougher hard herbs such as ROSEMARY, SAGE, THYME, and OREGANO. These are all herbs that would probably be cooked when added to a dish.