When should I start to give veg nutrients.. I alwa...

If there are no nutrients already added to your soil mix you can start adding your veg nutrients at 1/8 to 1/4 the recommended dose. Remember auto flower plants require less nutes than photo period. If they respond well by showing growth slowly increase the amount over the next few weeks until they green up. I would also like to mention that your day and night time temperatures are very low which can be an issue causing the root growth and plant metabolism to slow down causing an iron deficiency. Due to this your plants are starting to turn light green/ yellow. If you are unable to increase the temperatures you can do a a foliage feeding with a product that contains iron. Start with 1/8 recommended dose. Twice a week. then increase dose to 1/4 until symptoms disappear. Do not spray in full sun do the feeding before the sun comes up or before the sun goes down be sureto get the underside of the leaves where the stoma are located. Happy growing your going to have some big girls.