Treatment with dormancy breaking plant hormones
Deeply dormant species, such as Trollius, can be made to germinate reliably by soaking in gibberelic acid, or in combination with other treatments, for example leaching (Hitchmough et al. 2000). Whilst this is essentially kitchen-level science, it is probably
Table 6.12. Typical percentage field establishment of prairie, wet meadow and dry meadow species given adequate pre-treatment (where necessary) to break dormancy and sown under ideal soil moisture conditions. Data derived from author’s experiments
|
Damp/wet meadow species |
Liatris pycnostachya |
Solidago rigida |
Aconitum napellus |
Rudbeckia subtomentosa |
|
Campanula lactiflora |
Schizachyrium scoparium |
Damp/wet meadow species |
Primula denticulata |
Silphium |
Lychnis chalcedonica |
Primula florindae |
Solidago speciosa |
Polemonium caeruleum |
Stachys officinalis |
Sorghastrum nutans |
Primula vulgaris |
Succisa pratensis |
Ranunculus acris* |
|
Damp/wet meadow species |
Rumex acetosa |
|
Astrantia major Thalictrum aquilegifolium |
Sanguisorba officinalis |
|
Trollius europaeus |
Dry meadow species Buphthalmum salicifolium |
|
Dry meadow species |
Daucus carota |
|
Centaurea scabiosa |
Dianthus carthusianorum |
|
Hieracium aurantiacum |
Lychnis coronaria |
|
Malva moschata |
Primula veris |
|
* When sown in winter. |
Origanum vulgare Papaver orientale |
Salvia nemorosa |
too complex for use in practice. Jelitto Seeds offers chemically treated seed (Jelitto GoldNugget Seed®) of a wide range of deeply dormant or erratic nondormant species. This is more expensive than dry seed but gives very predictable results.
Germination requirements of a wide range of herbaceous plants are given in the Jelitto Seed Catalogue (Jelitto 2002), although, in some cases, germination is more erratic in field sowing than indicated, as recommendations are based on germination under controlled nursery conditions.