I can't imagine that there is anything there that is harmful for your checked luggage (well maybe if the pH down is too strong an acid)... but I can sure see the TSA getting nervous about it all.

I would send the liquids via UPS ground or better yet (if they fit) the USPS flat-rate box

I don't know what's in your kit (that is a very nice surprise!) but if there are any kind of fertilizers in there--some will trigger the bomb sniffers and your luggage will get extra attention. :)

Thanks guys!! I think I am going to try to take a chance. The nutrients are still factory sealed. The pH bottles are each half, but I think if I keep it in the plastic, maybe no sniffing hounds will be the wiser. The lettuce seeds are still in an unopened package so they won't think I replaced them with the "other" kinds of seeds. I don't want to ship it down ahead of me, because I want to present it as a surprise gift.
I think I'll just put a letter to the TSA in my luggage explaining what it all is. I'm sure no drug traffickers have ever thought to do that and they will totally bl like "oh, ok, no problem!!" LOL. I can be naive at times. I'll post back to let you know if it works in case people in the future have the same questions. I'll mention if I'm posting from home or from the slammer. :) Thanks again !!!!!

Why don't you call the airport and ask them?