Sweet peas have extremely tough, thick seed coats. Graham Rice, in
The Sweet Pea Book (tons of information about all kinds of varieties, and beautiful images….a sweet-pea lover’s dream), recommends pre-soaking. Unsoaked seeds can have extremely variable germination rate – from one week to a month – by that time, a less patient gardener will have given up hope and tossed the soil back in the bucket, or into the compost…
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