No Jay,
Thats tho reason you put Liln dried sand in the joints, it's sometimes called sterilised sand noththing can germinate in it.
The reason weeds etc grow in the block joints it because during the year the sterile sand is erroded away by wind, rain and insects etc. The atmosperic dust, builds up in the slot left by the missing sand and any seeds that rest in it germinate. This is also why the weeds easily wash away as a well laid block drive will have no growing plants/weeds in the sub base there all in the top 1/2 inch