I've tried planting Earth Seeds and Minicio Seeds on Fertilized Dirt, and every time they stay planted only for a few seconds before the seed pops off the ground. This happens even right next to a glowstone block (light level 13):
Vanilla seeds like potatoes and carrots grow just fine.
Running Magical Crops: Core 4.0.0_PUBLIC_BETA_4b and Magical Crops: Decorative 4.0.0_PUBLIC_BETA_4a in Minecraft 1.7.10 (Project Ozone 2 Reloaded mod pack).
Best Answer
IIRC, you have to use Agricraft (sticks and trimmers etc) for almost every plantable in that pack (with a few exceptions).