Episode-2620- James White on Hydroponics for Small Space Growing — 14 Comments

  1. Jack, a sincere thank you for helping us prepare our mindsets these last 12 years for what may be coming

  2. Has anyone tried using Jiffy Peat Pellets in a kratky seed starting setup?  I took a chance since they are much cheaper than rapid rooters (36 for $3 vs 50 for $17) and have had very poor germination after a week.  I’ve planted various greens and have only had 2 out of 30 germinate (tatsoi and mizuna).

    I have a feeling that the pellets too wet even with just the bottom of the cut touching the fluid.  Any thoughts would be appreciated, even if the answer is buy the rapid rooters.

    • Hi Nick,

      Jiffy pellets can perform poorly because they have two related problems…

      1: They tend to be too wet, drowning your seeds

      2: They tend to grow mold faster than seeds

      Both problems can be somewhat mitigated by adding hydrogen peroxide to your water.  Use food grade hydrogen peroxide if you can find it, the stuff available at drug stores contains stabilizing chemicals, some brands even use organophosphates.

      Below is a link to a good article explaining the benefits of hydrogen peroxide and instructions on how to use it.  Note you may need to double or triple the concentration to overcome the inherent problems in Jiffy pellets.

      Also note that Jiffy pellets are held together with plastic netting which can inhibit root growth, and doesn’t breakdown in soil.  Best to remove the netting when you transplant.

      • Thank you very much for the reply.  I had a feeling that something wasn’t quite right.  Looks like it’s time to experiment.


        Thanks again.

  3. My apologies to Jack and the TSP audience for botching the podcast.  You wouldn’t know it from this episode, but I talk/present/teach for a living.  I would rightfully be canned for that performance because it was more confusing than clarifying.  Worse yet, I’ve likely scared folks away from hydroponics when, in many ways, it is actually easier than traditional growing.

    Please post any questions you have here and I’ll do my best to respond.


    Thank You,

    James White


    PS,  Jack, there’s something hinky between your website and my ISP (Cox Internet).  I have been unable to access your site since yesterday.  Right now I am VPN’d out to a 3rd party in order to connect.


      • James, am using the Hydrofarm Hot House you recommended. If using the heating mat from seed, do you recommend discontinuing use of the mat after the seeds have germinated? Or where do you put your sensor once the cover is taken off?

        • Andreas,

          Use the heating mat depends on the ambient temperature of your environment.  The mat bumps up the temperature by 10-20deg.  The optimum temp range for most seed germination is in the 60-85deg range.  These temps also work well post germination.  Lower temps = slower germination and growth.  Anything above 90-95deg will not ideal for seeds,  but maybe ok for seedlings.  Just watch your humidity levels at with higher temps, as it encourages mold growth.

          So anyway… Use the mat if it helps keep your seeds & seedlings in the ideal range, keep using the mat.  If ambient temperatures start getting in that range naturally, then there’s no need for the mat.

          Note that your lights will generate more heat than the mat, so it might be best not to run them at the same time.

  4. Jon,

    I can take pics or post links to stock pics already on the net.   Anything in particular you’re looking for?


  5. Didn’t get the email but I signed the petition and shared it on all my personal and business social media. Thanks for doing this!