Note that this is also a hotel, which has separate reviews at TripAdvisor. We visited here for the gardens. There are also seasonal outdoor art exhibits on the very green property. We took a quick look inside the chateau's public rooms.
The main reason for a garden visit here would be the more than one hundred varieties of tomato. We didn't have time to book a tomato tasting, but they do have dinners and corporate entertainment on that subject. They also seem to be partners with a dahlia-breeding company, growing a vast variety, which luckily don't all bloom at precisely the same time.
Note that this is not a historic garden, like, say, Villandry. There's a hint of counter-culture here, in a nice way. They are located very close (that is, if you have a car) to the TGV station for Tours, which may make it convenient for a short visit on the way to "real" Chateaux. We found the property quiet and pleasant, unlike the bigger and more famous chateaus. There is an admission fee, but the booth at the gate was closed. We paid later, and they lent us an English guide and history booklet up at the cafe/gift shop. (Like much of France, you can't get a meal outside regular meal hours here.) And the chateau is "out of town", so you can't cross the street to a restaurant.
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