Plant or keep in pots?

Plant or keep in pots?

I took some "babies" from my mom's huge lovely oak leaf hydrangea - growth off the main plant that already had its own roots forming, that I cut off and potted in some organically-fertilized potting soil, in 6" pots. The plants range from around 8" to about 18" tall. My question is, would it be better to let them get established in the pots for a while, or to go ahead and plant them where I plan for them to grow? My concern with keeping them in the pots is how easily potted plants get dry, and how much both hydrangea's in general and any new plant in particular needs to be kept properly watered. I'm afraid that one hot dry day could kill them. My concern with planting them is that I'm afraid it would increase their chances of getting some bug or rot or kid or dog damage. In general, what's the best way to proceed with newly dug hydrangea babies?
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My first little veggie garden

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Because you all do it so well!

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my grandfathers garden

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