Hardy Tropicals UK

Apologies if this is a stupid question but when one brings frost tender plants out into the garden to plant out for summer, do you keep the plant in the pot and simply sink the pot into the ground, or do you take it out of the pot before planting. The former would make life really easy come the first frosts when the plant can simply be lifted out of the ground, but I cannot help but think that the plant would not do so well as if it were allowed to "roam free" .

This year I have kept all my border plants in pots and simply sunk them in the ground. I have done this as I hope to move house however am surprised how well they are all doing.

i suppose it depends on what plants you are actually talking about and weather you wish to protect outside or not.
It is also possible that with strong growing plants they will root though the pot into the ground and may make it difficult to lift in autumn

Hi. I'm talking about plants like Washingtonias,Ensete Ventricosum, cycads, Phoenix Canariensis and Calistemnons.

Why not just leave them in pots on top of the ground? They are not going to take up much water from the soil if they are in pots in the soil. It might save confusion, misunderstanding and buyers trying to bargain them into the house sale.

All my tenders are in pots so I either pot on or leave them be rather than put in the ground. The only exception is my ensete hiniba which I'm trying to grow on but nearly lost it in early summer due to root rot so it's not doing much again.

I plant directly in the soil and then repot in the Autumn/Winter. I do this as the plants grow significantly larger and often don't fit in the original pot. Gingers, Canna and Ensete will grow considerably larger in a season and will not go back in the original pots.

It's up to you, but I would suggest that keeping a plant pot bound will restrict growth. If you are okay with this and like the idea of an easier lift in winter then go for it. However, like someone else said, there is a strong possibility that the plants with root through the bottom of the pot and lifting will be stressful for the plant as these roots will lost.