|
 The
RHS
Award of Garden Merit (AGM) exists to
help gardeners choose the best plants for
all-round garden value. Besides being one
of the highest accolades the Royal
Horticultural Society can give to a
garden plant, the AGM is of practical value
for the ordinary gardener. Every AGM plant:
- Must be of outstanding excellence for
ordinary garden decoration or use
- Must be available from nurseries, seed
suppliers or specialist growers
- Must be of good constitution
- Must not require highly specialist growing
conditions or care
- Must not be particularly susceptible
to any pest or disease
- Must not be subject to an unreasonable
degree of reversion in its vegetative
or floral characteristics
Every AGM plant has a hardiness rating.
This is intended to serve as a general guide
to growing conditions. The hardiness rating
is an integral part of the AGM, and should
be included in any citation of the award.
Hardiness ratings:
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H1
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requires heated glass
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H1-2
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intermediate between H1 and H2
|
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H2
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requires unheated glass
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H2-3
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intermediate between H2 and H3
|
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H3
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hardy outside in some regions or
particular situations, or which need
frost-free protection in winter
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H3-4
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intermediate between H3 and H4
|
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H4
|
hardy throughout the British Isles
in summer
|
H1+3
|
requires heated glass; may be grown
outside
|
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