I've found that, like alcohol and caffeine, limiting your weed intake directly before sleep seems to minimize the negative effects it has on the quality of sleep.
Based on fitbit data and morning grogginess, over two to four hours before sleep seems to be a good window, but it definitely depends on the strength, quantity, and how you're consuming it.
It wouldn't surprise me though if most of the negative associations with weed usage (laziness, lack of motivation, depression, etc.) are really just the results of a lack of REM sleep.
It seems to be a pretty important process as far as I can tell.