The seed heads of Phtyolaca americana is what it reminds me of.
Have a look at Lonicera nitida, comes in green and yellow variegated forms. Easy to keep to a reasonable height.
Watch out for molluscs. The seedlings which I got this year were destroyed in one night of mollusc mayhem. My fault I should have found somewhere safe from predators..
The ones sold by Homebase et all are versions of C. persicum and they are only hardy down to about -2c.. And then only in well drained soil.
There is a hardeir C. persicum from the Golan Heights in Lebanon, but it is not that easy to come by.
And if you are like me, then you will have millions of them all around! They seed if you do not get around to dead heading them.
And the grit inside the leeks is easy enough to remove when preparing for cooking. Slice off the unwanted green tops and the roots and stand the usable bits upside down in water, the grit soon drops out.
The pink flower belongs to Himalayan Balsam. A rather invasive annual.
Changed my mind, it is a Chelone. Senior moment, as I was looking at Phyostegia in the garden just before I came on.
2nd is Physostegia virginiana, the Obedient plant, because the flowers stay where you move them to on the stem.
Cannot help on the first, don't do indoor plants.
They are either Bullace (wild plums) or as you think Damsons. Some of the Bullace are nice enough to eat, bit others are incredibly sour. Damsons are tart. No fruit I can think of in Britain matches your description which is toxic.
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