Tag Archives: fertilizer

I’m Losing Seeds

I’ve purchased The Growing Autoflowers book I’m confused about the fertilizer dosages of 20-20-20. In all of my other readings the dosages are sooooo much lower such as 3-0-0 of liquid nutrients. As well as stating to reduce even that amount by 3/4. I’m afraid to use that high dosage do to the fact I’m losing so many seeds. Anything that you can tell me will be greatly appreciated.

— Susan

Hi Susan,

Thank you for your question.

We aren’t hard and fast on the fertilizer ratios, as a lot depends on your soil and other growing conditions.  AutoFlowers don’t need a lot of fertilizer, but they do need some.  That’s why we recommend only using a quarter of what your fertilizer bottle says to use.

If using good soil and good (not hard) water, we have seen good success with 20-20-20, but we recommend only using a quarter of the recommended amount on the bottle.  We have also seen good results with 18-10-10 (again, using a quarter of the recommended dosage on the bottle.)

Since you have been losing seeds, it could be due to your water and/or soil.  If the pH is off, or if the water is hard, it could cause your seeds not to grow.  It also could be the seeds themselves.

We have a few questions to see if we can help you:

1.  What type of soil are you using?  Does it already have nutrients added?  Is it organic?

2.  If starting with rock wool, have you been correcting the pH first?

3.  Do you have hard water?

4.  Have you checked the pH of your soil and water?

5.  If using tap water, do you allow your water to sit out for 24 hours to release the chlorine before watering you plants with it?

6.  Are you leaving excess water in the drainage trays after watering or are you pouring that excess water off?

7.  Are you allowing the soil to dry a little between waterings or are you keeping it saturated?

8.  Are your seeds from a good reliable source, or from a friend?

9.  Have you been able to successfully grow any of your seeds yet?

If you can answer these questions, maybe we can help you figure out why you are losing seeds.  No guarantee, but we’ll be glad to give more information that might help you.


Dr. Grow

Simple Fertilizer?

I’ve been reading your Growing AutoFlowers book.  You recommend mixing fertilizers from several bottles to get the exact nutrient mix.  Can’t I just use a food for veg and a food for bloom in lieu of buying and mixing from 5 bottles?


Hi David,

You can be flexible about nutrients, but must be careful not to over fertilize.

Yes, in theory you could just buy one bottle of nutrients for veg and one bottle of nutrients for flowering.  Remember, only use 1/4 of the amount recommended on the bottles.

The real trick is knowing when to switch over with your AutoFlower plants.  With regular Indica and Sativa plants, you have to force them into flowering by reducing the amount of light they receive down to 12 hours a day.  When you do this, you are choosing when the plants switch into flowering mode.  Therefore it is easy for you know when to switch fertilizers.

With AutoFlowers however, you never change the amount of light and they start flowering whenever they are ready.  You are not telling them when to flower.  Therefore, you will have to watch your plants closely to see when they are showing signs of beginning to flower.  You can switch over to the flowering nutrients when your classes are starting to show the first signs of flowering.


Dr. Grow