Fertilizer for an indoor grow with ground soil

[Mwerk]

First of all, this is kind of an indoor AND outdoor question. My setup:
I have a shed, bare floor that is well protected from the elements and gets a fresh breeze constantly from a small fan. Right now we're flowering:
1 Green Crack
1 Afgooey
1 Bubba Kush
1 Pineapple Thai
and 2 Romulan X Purple Kush crosses

The plants are in a raised planter with well amended soil, the Mycorrhizae on the farm this shed is built over is very well developed, our natural soil is great and I amend it with fir mulch and peat when it needs to be aerated.

I've got a single 400 watt MH/HPS ballast and for veg I use MH, for flowering I use HPS. They've been flowering for the last 2 weeks. My two questions:

1. What (preferably organic) fertilizer would be most easily absorbed in the last 3-4 weeks of flowering just to help flesh out the buds?

2. What (once again, preferably organic) fertilizer can I put into this soil that will slowly release nutrients and make them available to the next batch?

I'll be planting the clones immediately after I cut and dry, so I want to work something into the soil to make nutes available to the clones from the moment they tap into the soil.

Thank you all for reading my first (but not last) post on this website! I've been lurking for almost 5 months now and I love this forum!

 

[HB Rob]

For now: High P guano, though I would personally top dress around the second or third week to give it time to start breaking down so as to be fully available for flower formation.

For later: Earthworm castings and kelp meal. Both products together will revitalize nitrogen, potassium, and micro nutrient stores as well as add organic material to keep your natural rhizosphere strong. Castings and kelp breakdown gently so have no fear putting clones straight into the soil.

You can still get more diverse in your amendments if you choose, but those three ingredients will see you 100% of the way through. GL!

 

[Mwerk]

Nice! Thanks for the tip.

I was actually just thinking, when I add more organic material next I should head to the bait shop and throw a couple of earthworms in there, I'll still add some castings but the crawlers could aerate the soil and put more castings in in the long run. The raised planter has no bottom, I put some heavy gauge chicken wire on the bottom to keep gophers from getting to it (don't know whether or not they like it but better safe than sorry).