Northern Hemisphere: Aug 1st
Southern Hemisphere: Feb 1st
Colors: Red, Yellow, Gold, Brown, Orange
Decor: Wheat stalks, Grains, Oats, Corn, Apples, and other summer veggies and fruits.
Lammas is the Neo-Pagan holiday celebrating the last few weeks of summer. This is actually an Anglo-Saxon festival to mark the annual what harvest. However, it is important to note that this founded after the Christianization of the area, so while this is a Germanic Tribe, it's not actually sacred to these particular pagans.
So How Did it Become Anlgo?
There is Lugh, the Celtic Master of Crafts, but he's more like the Roman's Mercury, not harvest. He is depicted with a ray of sunshine behind him and he does relate to making things, so... maybe, but it sounds more and more like a stretch. Now, there is lore that states his foster mother, Tailtiu who IS the Goddess of Agriculture. He was actually performing funeral rites after she died from exhaustion while plowing the fields for her people. It's also been suggested that this was more about the Goddess Eriu, who Lugh was intended to and during this time the older Kings would "marry the land" and look after her.
The other Germanic denominations don't have anything either. So, it sounds more and more like an accidental linguistic barrier. The name of the month was Lunasa, so both words do have a similar root and like with many pagan traditions, the months and pantheons were often likened to each other. The more and more I read about him, though, the more and more I believe it had little to do with him as opposed to what he did.
So... The Anglo's?
Now we're tackling how this became the celebration of a harvest and not the solemn funeral of Tailtiu. It was likely they people could sacrifice the first of their harvest to her by baking bread and hoping for a better harvest the remainder of the harvest season. This was later adopted by the Anglo-Saxon Christians and continued to be carried on by the Catholic Church on through the Protestant separation.