When to add more lights

Hi guys,,just wanted to know when does the plant benefit the most from extra lights or more wattage. Let's say I use a few Cdm 315w lights for veg,,I flick them on to 12/12 but don't have the 2kw lights available until a week or 2,,the plants don't produce buds straight away so I was hoping that they would be ok for a few weeks before the increase and that it won't effect yield..any ideas on how this works ? Cheers for your time

More light is always better in alstages,early flower you will get more grow and stretch,for me I like more light week 4 and on

The first 14 days of flowering should not be influenced that much, on you using the lights you have mate, until you get the bigger ones in my experience, as mentioned they tend to stretch wildy in the beginning, so from week 3 or 4 would be good time to change to bigger lights on them ladies...

Have a mellow day...

Cheers for the responses guys,,hard to find out exactly when is most effective,,fingers crossed it doesn't affect yield too much then,,,