Your statement is partially correct, but not entirely.
As an animal embryo, the seed, still closed, is already formed, with the distinction between root, stem and leaves. Tiny but already there are.
All the rest of the seed (in this case two cotyledons) is a kind of food dough, and serves as a food reserve for the seedling, until the time of rooting and the achievement of energy independence.
As animals, the plant seeks, first of all, water. The first need of water is determined by the need to break the skin that closes the seed. If there is no presence of water, the seed dried and does not sprout.
If it "feel" the water, the seed drinks, swells and the skin breaks down. At this stage we can also say that the seed is aware of where it can find water. I do not think that they have been studies done on the awareness of the high and low (orientation). On the edge of rivers and lakes the seed can also find favorable ground above itself.
The direction of the water determines an effort, which can also lead to the rotation of the seed in the right position to emit the radicle towards the water (and the earth). In this time the embryo "eats" the nutritional reserves contained in the seed.
Then precisely they decide which direction to go in. When the place and position are correct, the seed has open and the part to eat is almost eaten, then more light. The radicle grows to first, both in size and as the length. It hooks to the soil and establishes a firm basis. Starts to drink directly (and not by absorption of the tissues of the seed) and starts to push out the seedling, typically in the opposite direction.
The seedling "feel" the light energy and go to that.
If the plants have ability of decision or not, has not yet been established. But to me personally it seems that a functional DNA must be able to allow each subjet to handle each situation (consistent with its structure) in the best way to itself.
This seems to have been ascertained for the animals. A certain capacity of thought, namely to make decisions, is absolutely functional in a huge energy saving on the need for encoding and on the structure of DNA
I know little about the life of the colonies of ants. But I know all about bees. A swarm that is detached from the hive to found a new colony, it also stops two or three times. Sends forward scouts, followed by architects and, if the place is right, the architects have a network, and bees wax begin to build.
Your mention of the ants is not sufficient to me to find similarities.