Overall I agree with the others...Layena pellets is fine for hens 18 weeks and older.
As to making them lay, no and yes...depends upon the breed.
If you have production birds like Production Reds or Red Sexlinks, I have read studies that show those commercially hybridized birds do better if they are started on a layer feed to help them ramp up to laying as the bird does need enough calcium to begin to lay.
More "heritage" breeds take longer to lay, so you may delay the start of layer rations.
Waiting for new pullets to lay is sort of like watching a pot to boil...the more you watch the longer it seems to take. Do keep an eye out for odd spots where they may be laying. I've often had a new pullet sneak away into an odd place to lay eggs. While I think she is just slow to start, she is piling up eggs in a hidden corner.
Another variable is the heat...if it is really hot in your area, that can delay the start of lay. You also are fighting shortening days, so if the birds hormones/body hasn't ramped up to begin to lay before the daylight gets below 12 hours a day, they may not lay until early spring. It is always dicey with March chicks which way they'll go...whether they start to lay before the winter sets in or after.
Commercial production breeds tend to come to maturity early and will lay that first winter in spite of the shorten light.
One way to ensure laying would be to add lighting to the coop such that the birds have 14 hours of straight lighting in order to begin and sustain laying (12 hours is needed to begin, but it takes 14 to keep sustained laying).
Hopefully you'll have some eggs soon.
LofMc