• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

One out, one in...

The last of the hippeastrums go out with a flourish as we prepare for the rosemary trial

Rosemary grown under coverNow that the weather is warming up nicely the rosemary plugs that we over-wintered in the polytunnel are putting on plenty of growth. Many of them have also put on a show of early flowers, but we trimmed all the plants last week to keep them bushy and prevent them becoming leggy.

We will keep an eye on growth, but hopefully we won’t need to pot them on before planting out on the trials ground during May.

The trials field here at RHS Garden Wisley is a very open site - so the plants won’t be short of sunshine, and we’ve chosen the highest bed on the trials field to ensure we have good drainage throughout the three years of the trial. The prostrate types will be planted in containers to show off their trailing habit.

Last hurrah for hippeastrums

Click to enlarge: Hippeastrum 'Samba'In the meantime the hippeastrums, or amaryllis, have now finished flowering in the glasshouse except for a handful of late-flowering cultivars.

We had some lovely blooms in the Hippeastrum trial this year: some of the best performers included ‘Picotee’, ‘Adele’ and chunky, flamboyant ‘Samba’.

Click to enlarge: Hippeastrum 'Picotee'As the flowers continue to die back we will cut the flowering spikes, but continue to water and feed them through the summer to encourage good leaf growth, and some will re-flower. The bulbs should bulk up over the next six months before we encourage them into a dormancy period in the autumn.

Useful links

How to grow hippeastrums
Grow your own - rosemary
Find out more about RHS Plant Trials

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