You're Correct!
It is really important when you play your wedges that you are making a downward striking action with the club head, to hit a sweet shot with your wedges.
If you are catching the ball on the up swing, you will tend to either, hit the top of the ball and hit a lower shot, or you will just strike the ground first and the club head speed will be transferred into the ground rather than the ball. Doing this, you will now end up hitting the ball short of the target. If you want to get your golf wedges closer, work on striking down on the ball.
Here is a great drill in order for you to achieve a downward strike. Ensure that you set up with the ball in the centre of your stance and make sure your hands are just to the left of this (if you are a right handed golfer), so that your hands are set forward. Work on creating a forward lean in the shaft of the club, so that the handle of the club is closer to the target than the club head is. To do this, make sure that from your left shoulder, down your left arm and then down the shaft of the club is one straight line and this will ensure your hands are in the correct position, and your hands are forward of the club head.
Position your head so that you have your nose just left of the golf ball and you should now find that you have slightly more weight on your left side. This is going to promote you to take the club head back slightly steeper on the back swing and as you come back down towards the golf ball on your down swing, it will give you a nice angle of attack, so that the club head is striking downwards on the ball, striking the ball and then the turf.
If you have trouble doing that then remove the ball from this exercise and just put a coin in its place. Now a coin is only a few millimetres high so you have to be extremely accurate to do this drill well and if you practise this at home you should find it much easier the next time you come to play your wedges. Place the coin in the position that the ball was in and now work on making your swing and hitting the coin. If you hit off a mat as you do this, it will also really help you. If you strike the ground slightly early on the mat, or carpet, the club head will bounce up and you will totally miss the coin and if you do not swing down low enough again you will totally miss the coin. This is a really good drill having you crisp up where the low point of your swing arc is and it needs to be where the coin is. The coin simply is representing the ball and if you can hit that coin you will have no problems in hitting a great wedge shot.
Sorry Try Again! - See Explanation Below
It might seem logical to make an upward movement to get the ball up into the air, but as golfers we hit the ball off the floor, so we cannot get the club head any lower than the ball already is, to make an upward strike. If we make an upward strike towards the ball we are now moving the club head up off the ground and we are going to hit the top of the ball and that will give a very low shot which will fire across the green and you will have very little control on it.
Sorry Try Again! - See Explanation Below
If you strike the ground first with the club head before the ball, then all the speed will be delivered from the club head, into the ground and you will now end up hitting the ball with very little club head speed and the ball will not get to the green, it will finish short.
Sorry Try Again! - See Explanation Below
Work on that coin drill. If you get more accurate hitting that coin you will find that your golf wedges really crisp up and you will hit them a lot closer to the pin.