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guthman

I did not flush an soak my rockwool, what do I do now?

Guthman
12 years ago

Hello, I am very new to gardening. I've read alot now about different techniques and theories.

Last week, after reading for a while about hydroponics, I decided to get to action and I bought a slab of rockwool germination cubes.

Enthusiastically I started planting seeds (21 different types) in the rockwool last Sunday and moistening them with the intention of transferring to a DWC system later on.

Yesterday I read, to my surprise, that it is very necessary to flush and soak the rockwool cubes before using them if you don't want constant pH problems while growing.

I tried to get pH test strips as soon as I found out, but the drugstores were already closed and the hospital drugstore didn't have any. I'll get some today, but I wanted to post here first.

Yesterday I dripped all the cubes with slightly diluted white vinegar as a desperate measure. Not sure if the effects were good or bad, but so be it.


Now, finally the question I have: What do you guys recommend?

1. Can I flush and soak the cubes with the seeds in them? As some of the seeds are very small (like oregano, very very small) and close to impossible to get out.

2. Or should I throw away the cubes and start fresh?

3. Should I try to get as many of the seeds out and flush and soak the cubes?

4. Should I do something else?

5. Have I damaged my seeds by exposing them to the high pH of untreated rockwool and subsequently to a lower pH of vinegar?

6. Can I still use the seeds or should I throw them away?

I'm not sure if this belongs in the hydroponics forum, but I figured that rockwool germination is most used for hydroponics systems?

I think I mentioned all the relevant information, but if I omitted anything, let me know!


Just to mention, I planted the following seeds:

Basil Spice

Basil Sweet

Basil Lime

Basil Nufar F1

Greek Oregano

Chilli Ring Of Fire

Chilli Scotch Bonnet Yellow

Chilli Habanero

Chilli Numex Bailey

Selery

Shiso

Paprika

Water Lemon

Quadrato d'Asti Rosso Pepper

Garlic Chives

Dr. Carolyn Tomato

Alpine Strawberry

Red Strawberry Guava

Cape Gooseberry

Sweet Granadilla

Pink Velvet Banana

Comments (6)

  • Guthman
    Original Author
    12 years ago

    I don't see any way to edit my message, so here's a picture of the setup:

    http://www.guthmangroup.com/img/IMG_20110524_115134.jpg

  • homehydro
    12 years ago

    Guthman
    Wow, you have started a lot of plants. There will probably be people that disagree with me (but this is just my opinion), you don't need to pH anything with roockwool. Perhaps if that was all you were growing in, but not just for starter cubes. You mentioned tossing out and starting over, that would be a huge waste in my eyes. There is no reason to toss something in the trash when you can learn something from it (especially when it dosen't cost anything extra).

    At the very outside you can start new seeds in rockwool, and keep what you have going (no reason to toss them), to see what happens. But in my opinion, you wont have any problem getting the seeds started unless your temp, and/or humidity is off.

  • ethnobotany
    12 years ago

    I have to disagree with homehydro on this one. You should probably start over unless you feel like you cannot afford to do so. The pH being wildly thrown around has surely adversely affected plenty of those seeds. I have a hunch that quite a few may not even sprout (although I could be wrong).

    If you want less headache, less worrying, and a higher probability of success, restart. There are already so many "ifs" in hydroponic growing, that if there is any way you can block a probability and make it a definite, you should probably do it. The only reason NOT to would be for saving cash.

    Also, about the rockwool cubes: I would soak them. Some say you need to, others say you don't. I say you most certainly should soak the rockwool cubes in a pH balanced water. In fact, I reccomend soaking them in tap water or RO water for say 10 or 15 minutes. Pull them out of that water. Get some new water, and make sure it is as close to 7.0 pH or lower as you can get it. Soak them in this water for 45 minutes. That should do it, and honestly you will be better off because your pH will already be shifty, especially if you are using hard tap water. Using this method of pre-treating the rockwool cubes, you wil have less trouble in the long run!

    If you don't want to mess with getting a pH perfect solution, you can actualy purchase rockwool conditioner that apparently many people find to work great. Some of it even includes a great balance of nutrients for your seedlings.

    Theres my 2 cents!

  • homehydro
    12 years ago

    I know that a lot of people swear by flushing and pH balancing rockwool, and if I'm not mistaken the directions even say to do so. But I just thought I would elaborate more on my reasoning. I don't use rockwool much at all, all I use it for is seedlings that I start in the one inch cubes, then transfer into another growing medium (usually coco chips). I started seeds in the rockwool before I ever knew you were supposed to pH balance it. So I just never did, and I don't have problems getting seedlings started in the rockwool cubes. Well except for spinach, but I cant attribute that to the rockwool scene I cant get them started in anything else either (coco coir, on a wet paper towel, in potting soil etc.).

    But even if you wanted to start over, no problem. Though I cant see any reason to throw away anything. What could it cost to just keep the cubes you already started wet, and starting some new ones anyway. Then you have something to compare results to, and would be a good learning experience.

  • Guthman
    Original Author
    12 years ago

    Thanks for the responses. I finally bought the test strips today and found out the moisture in the cubes is in the range of 7-8. I tested my tap water, which turned out to be around 6 so I moistened the cubes with tap water and the pH is around 6 now, which, according to some databases is the sweet spot to cater to as much different plants as possible.

    Now it's time to wait and see what will sprout and what will not!

  • Dan Utinske
    2 years ago

    I made the same mistake you did; should have known better!! Quick question, how did you moisten the cubes? I need to do the same, not sure if they will wick enough. I have an indoor Tower Garden and when we first set it up 3 months ago we did soak the rock wool for 30 minutes; just forget this time. Anyway we didn't even see anything on the pH until after I put the seedlings into the tower @ 3". We now have a jungle and we give away so much salad produce from the tower, seems the more we cut the faster it grows. Now were going to add peppers around the bottom cups, sweet peppers, Jalapeno Peppers and Peppercorn plus Dill and Cilantro. I just hope I can salvage because I don't want to waste the seeds.