Basil Seed

Does anyone know when best to harvest it? I have so many that I've allowed to finally go to seed after all that summer deadheading, but am not sure of the best time to try to harvest/save it. Right now the seeds have formed but the heads are still green.

The seeds are in the bottom of the seed head, so you may want to put something like cloth tacked down in case they fall out on their own and get lost.
It is hard to say when to do it since the individual seeds even in the same pod will ripen at different times.
For sure when they turn brown and thin is the ideal time, but also you could lose a lot waiting that long.
I sometimes take a bowl and hold it under the seed head and flick it with my finger. The ripe ones will fall out into the bowl.

Temps have really dropped here since yesterday, & I'm sure our 1st frost isn't far off at all.

If frost is predicted, should I try to cover these plants until the seed ripens, or cut off the seed stalks & bring them inside to continue ripening. I don't know if they need to ripen on the plant or not.

Gee, If you have a lot of them I suppose you will get some seed that is far enough along to ripen inside. The problem would be if they are too small to even be viable once dried. Is there a way you could bring a few inside as plants into the garage or something root and all and let them continue to grow a little?
You also could cover them if you have enough warning of a frost. Throw a light cloth over them or even some cardboard leaning ove them propped so as not to smash them.

If even some of the heads along the stem have turned brown & dried out, then my experience is that the seeds in the rest of the heads will continue to ripen inside if you pick the stem. Completely green seed heads don't seem to do well, but if they've even started to turn in color, they should be fine. Otherwise, I'd protect a few from frost as suggested. BTW, although daytime temps are lower here too, the forecast says no nighttime low below 43 for the next 10 days, so you might be OK too.

How about the old nylon stocking trick? I find knee-hi's work best. Six knee-hi's for $1.00 at the dollar store; they keep the tips of the plant a little warmer too. Tie them on with twistie ties (used or new) or an old clothes pin does well in a pinch. This way none of the seeds can escape till you open it up. I just clip the stem off underneath if it goes to frost; and you can do other things besides watch for the seeds to mature.

~* Robin

Now that's something I never thought of!!! Thanks NatureWalker!!

Just make sure you don't have any nosey pets around. I did that once to some zinnias I wanted to protect from finches that were stealing the seeds. After carefully twisting all the pantyhose into place I went inside. Later I looked out to see these colorful little balls in the yard. My playful doggie had snipped all the heads off panty hose and all. ARGH!

A little powdered cayenne pepper sprinkled on top works wonders for that... it sure does with stray cats, skunks and 'possums. And the untrained puppy from next door.

~* Robin