We, like the slaves of the householder are quietly bidden to wait. What a rich theme this is. I recall the words of Moses to the Israelites as it seemed they were trapped by the advancing Egyptian onslaught behind them and the sea in front of them. God has got that all organised. I return to my definition of weeds.
Weeds are just ordinary plants which are particularly prolific and hardy.
By growing quickly they stop other plants from growing into the plants God created them for. So we have two little mini parables between the parable of the good and bad seed and its explanation. The parable of the mustard seed and the parable of the leaven. Both the mustard seed and the yeast exist for other parts of the creation. The tree which springs from the smallest of all seeds becomes a safe haven for birds.