Good questions regarding re-amending, guys.. its bit of an art and science I suppose.
I think this bears repeating, as it was well written and points out some important factors to not overlook:
"I would expect the amount to top dress in a no-till situation would depend greatly upon the size pot you grow in combined with the amount of time that you veg'. I also think that top dressed amendments would take a bit longer to become plant available (not as much exposure to soil biota compared to being mixed into the rhizosphere), so timing of application should also be considered..." -@waktoo
Other big things that I factor in include the
strains' metabolisms and
soils' engine power / life force, as well as the results I want to achieve..
Amount of time I have to or plan to cure is another.. the longer the cure the more you can push things a bit.
For example, on 200 day cures, I like to push my kelp to 2% sometimes, as it increases potency, but if I have 3 weeks only, then ~1% it is..
And whether growing for free medicine or recreational flower competition / concentrates may influence my tactics a bit too..
But overall, general rules of thumb I adhere to are:
if growing in small pots, I cut my recipe amounts in
half in the rhizosphere or global mix, and maybe I add a spike instead, for the plant to tap into shall it see fit.
(Btw, to me, small equals 15 gals and under or so)
Sativas, I do a bit less P and a bit more N, and they veg longer, and flower longer, so I do a bit more slow release ingredients and go a bit chunkier if I can.
Indicas, and faster heavier eaters, I can be a bit more aggressive with.
Also, the biggest factor of all is probably the initial recipe followed or created.
Because if doing 2% kelp, just for example, you may not need to add any for 3 or 4 cycles, but other strains may like smaller doses more often and require a 1/2 cup each round or each month or two..
This is where working with the same strain for years can really help.. for those working with new strains, I suggest starting at the low end, going with bigger pots, and see if roots attack the bonus spike you put in..
Another question I have is since I use a planter bed, do you top dress the whole bed or just around the plants? I dont have enough castings to cover an entire 4x4
Well castings are highly bacterial, right, and aid young plants the most, as they won't get any botrytis or stem rot before they develop woody stems, so if young plants are going in the no til, I would go around the stems, but if older bigger plants were going in there, I would probably create little holes the size of toilet paper rolls and plug em up with castings, in and around the plant, just outside the rootball.. top with a fungal food and then mulch.
Also, depending on the breathability and size of your bed, you may want to tea up your corners, and dry spots, and stretch that EWC in a tea a bit, especially if there is no mulch, which should be a must with any size plant, to avoid uneccesary light and wind erosion...
Another factor to consider is the performance of the bed, and the amount of castings in it already.. I like to use pure castings (one year refined) vs vermicompost (6 wks refined) which makes it more potent, and keep it around 10% of total volume.. vs 20% or 33% which to me, is a mistake when it comes to end product performance.. note: thats not including the aeration I add to the worm compost, biochar being my fav. I like to make my castings 50/50 aeration and pure potent EWC.
So whether employing the use of mulch, biochar, AMF and other fungals are big things to address in conjunction with this, as well as plant sizes and potency of the castings. Are they amendend? aerated? Can they fight off some drought? And lastly, potency, is it finished and refined..
-D
