Red robin - not growing well

Hi there.
I planted some red robin hedging around March and had a few plants left over that I put in pots.
The ones in the ground have lost their "vibrancy" and faded a lot in colour whilst the ones in the pots have stayed strong red and green. In the 2nd picture I have put in one of the pots for contrast.
Am in Ireland so they got loads of rain they are south facing in full sun.
Any ideas what went wrong with the ones on the ground? And best next steps?

Thanks

 

Nothing has gone wrong, probably. The young new leaves in spring have the vibrant red colour but they fade to that lovely coppery green as they age.

Once your hedge reaches a height and width where you start to clip them regularly you'll get new red growth in spring and whenever you clip. You just need to give it some feed every spring - eg pelleted chicken manure - scattered about the roots and be patient.

 

Ok. Thanks for that.
Why would the ones in the pots have retained their colour and vibrancy though ?

 

Different soil? Different feed and water levels? The ones in the ground having more space to spend energy putting out new roots?

 

You may be giving your plants in pots a bit more attention such as more watering perhaps? The ones in the ground would benefit from having the area around the base cleared of the surrounding plants which will be competing for water and nutrients. Ideally, creating a distinct border with added organic matter would help the roots get established. Also be sure to keep the soil moist during their first growing season. Once the new red leaves change to a coppery colour, the mature leaves should be a healthy dark green if kept well watered.

 

I agree, competition from the surrounding grass and weeds could be a factor.

They are quite picky about conditions so what else might be different?
Sun - has the one in the pot also been in the same full sun?
Moisture - they don't like to be too soggy so if it's been very rainy and the soil has been waterlogged, the one in the pot might have had better drainage.
Exposure - Apparently they like a sheltered location. Has the one in the pot been more sheltered from wind and weather generally? Perhaps it's been standing close to a wall and the ones in the ground have been more exposed.

More info. on what they like, to help you get to the cause of the issue: Photinia × fraseri &s;Red Robin&s; | Christmas berry &s;Red Robin&s; Shrubs/RHS Gardening

 

Thanks everyone. Really appreciate the advice.
The pictures are a little deceptive - there is lawn at both sides of the plants but actually very little vegation at the base of the plant. I normally keep it pulled.
The ones on the pots were in exact same location.
We have had a lot of rain this year so waterlogging could be an issue. Is it possible to do something to help drainage?
I gave them a feed a last week after posting the question and it has already "jazzed" them up a bit so maybe just weren't getting what they need / rain was washing away the nutrients.
The edges of some of the leafs had turned black - is that an indicator of something?