Please recommend a rose grower

I'm a newbie rose grower and bought 5 plants from 2 nurseries in the autumn and only two will make it through to next season, and possibly a third.
I would prefer to buy potted plants rather than bare rooted ones.
TIA

I'd be speaking to those nurseries about replacements so long as your care was up to scratch. Why do you think you lost them? Maybe we can help with that?

One bare rooted standard had only one main short root plus a couple very spindly rootlets - I'm surprised it got to flower at all. Another in a big tub on the deck had all the canes bar one die back to the bud union - the one cane put out a small twig that had 2 yellow flowers rather than the dark yellow and red variegated flower it should have had - maybe it was more frost tender than I was aware of? The third dodgy plant has has mould pretty much since it arrived which spraying has only just dealt with, but all the buds has fallen off.
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Well, nonumbers, as a new rose grower perhaps I could give you a little bit of advice. Buying roses in the autumn (I hope they were potted) was probably a little unwise to the uninitiated. The best time for planting roses is the winter - and the most cost effective is bare rooted. The issue is getting them into soil or mix pronto so the roots do not dry out. Frankly, there is very little point in paying garden centres for potting up your roses if you are just going to pull them out and plant them. Ever noticed how they are tied into the bag and the mix just falls away? That's because they have just been put in! The benefits come (of doing this) when the rose starts to stir - putting out tiny white feeder roots - which are exceptionally brittle and tender and should not be disturbed - and the rose has some food to start to grow.
The best thing to do is follow the instructions implicitly and plant your bare root immediately you receive it. That way, it can settle into its new home without further disturbance. A good nursery will provide well documented advice - usually with illustrations - to help you on your way. They will also provide you with the needs of the rose once it starts to grow. Roses are gross feeders and require regular feeding and long, deep watering. So what has happened to yours that you are losing them? Did you prune them back in winter? There is one possibility that, if you have done everything else right, that is the cause - and that is the exceptionally wet spell we had in spring. Whilst roses like deep watering (as opposed to sprinkles) they certainly do not like wet feet for extended periods of time. This could have been the issue. Don't be put off by bare roots - gardening is expensive to do properly - and any savings you can make - helps towards something else. But - I am a proponent of buying quality - buy from a quality grower and use quality products - it pays off in the end. Having said that - I would like to recommend you look at Tasman Bay Roses website (w. TBR.c. z)
and be well prepared and ready to plant when your roses arrive in about July.

In my experience you can't kill roses. Mine have survived being left bare rooted in a bucket of water for two years before being planted out and inadvertently being sprayed with weedkiller! And they all survived. Sorry, can't help you OP.

But Tasmin Bay Roses are great.

All the plants came pruned with canes just about 15cm. The only rose knowledge I have was from my aunt in south England who never pruned her roses prior to winter, just dead headed them. Once the frost and snow had gone and new shoots started appearing, then she started cutting back the old growth.
They've been fed and seasoled until they squeak - maybe too much? and sprayed for mould, bugs, and black spot.
Oh well - back to the drawing board - so to speak, and thanks for the recommendation.

We've bought most of our roses from Wairere Nursery in Gordonton and the quality has been very good. You can buy on line or visit the nursery.

https://www.wairere.co.nz/Roses

Just to catch up - the rose that I tossed had apparently drowned - the soil in the tub was waterlogged and it had only produced one or two fine white roots. And yes the tub had a good number of drainage hole - so - my fault. The poorly standard in the garden was miserable from the get go, but some fresh leaves starting, but I don't think it'll do well. The other three are doing OK.