While Valorum is definitely correct, the specific details you recall certainly match Andre Norton's Star Rangers (1953). It is a short novel, rather than a novella (short enough to be published as an Ace Double and a novel-length omnibus with its prequel Star Guard) but so close I believe it's what you're searching for. Star Rangers was reprinted under the title The Last Planet when it was republished in 1955 in an Ace Double, and as Star Soldiers in the omnibus printing. A short novel may be close enough to a novella in your estimation that you might consider them the same.
In the story, the crew and ranger complement of a Patrol ship crash on a distant planet, so far from Central Control that it doesn't even lie on their charts. Their ship unrepairable, they prepare to make the best of the planet they find themselves stranded on, which they describe as "Arth type."
The comment on the greenery is when, scouting from the desert they landed in, they first see the native vegetation:
For that ribbon of vegetation was green! But the green! It had no yellow tint, and none of the blue cast it would have held on his own vanished Ylene. It was a verdant green such as he had never set eyes upon before—running in a thin line across the desert country as if it followed some source of moisture.
After a misadventure in an abandoned city with another party of refugees, who are in the thrall of a telepath named Cummi, they encounter some natives in the woods and discover they are-to telepathic senses-human:
Kartr caught the mind of the one who was trapped. It was human—but not Cummi. A stranger, hurt, alone, and very much afraid.
The natives make a yearly trek to the "The Meeting Place of the Gods" where all their people meet, which is the place from which the gods of their prehistory left:
"From the little I was able to learn there are only a few small family clans—but they unite once a year at—"
"The Meeting Place of the Gods, yes, that is a most interesting point. These 'gods' who departed into the sky—who were they, some galactic colony later withdrawn?"
This meeting place is indeed a large building from which the original colony ships departed:
Kartr, now that his attention had been directed, sighted it, an expanse of massive blocks only barely perceptible in the poor light.
Rolth cupped his hands around his eyes to cut some of the fire glare. "Let's have the visibility lenses, Kartr." And when he used those he added with a faint trace of excitement:
"It's huge—bigger than anything we saw in the city! And—did you ever visit Central City?"
Kartr laughed bitterly. "I saw visigraphs of it. Do you think we outer barbarians ever came so close to the fount of all knowledge as to see it in reality?"
"And what has Central City got to do with this?" Zinga wanted to know. "Were you ever there yourself?"
"No. But one can get a pretty good idea of the place from the visigraphs. And that building over there is an exact duplicate of the Place of Free Planets—or I'll eat it stone by stone!"
They discover that the Hall of Leave-Taking designates this planet as fabled Terra:
But Kartr's torch beam fastened on the sign carved on the nearest of the side chairs. As he read it he stood incredulous. Then he flashed the light to illuminate the marking on the next seat and the next. He began to run, reading the symbols he knew—knew so well!
"Deneb, Sirius, Rigel, Capella, Procyon." He did not realize it, but his voice was rising to a shout as if he were calling a roll—calling such a roll as had not sounded in that chamber for four thousand years or more. "Betelgeuse, Aldebaran, Pollux—"
"Regulus." Smitt was answering him from the other side of the hall, the same wild excitement in his voice. "Spica, Vega, Arcturus, Altair, Antares—"
Now Rolth and Dalgre began to understand in turn.
"Fomalhaut, Alphard, Castor, Algol—"
They added star to star, system to system, in that roll call. In the end they met before the dais. And they fell silent while Kartr, with a reverence and awe he had never known before, raised his torch to give more light to the last of those symbols. That bright one which should gleam in this place was there!
"Terra of Sol." He read it aloud and the three words seemed to echo more loudly down the hall than any of the shouted names of the kindred stars. "Terra of Sol—man's beginning!"