Seed Sowing Guide - Types of seeds
All seeds can be divided into categories which describe the plants growing characteristics, here is an explanation of what they mean.
HA - Hardy Annual
These seeds can be sown directly outside during spring and they will mature, bloom and seed in summer and finally die all in one year.
HHA - Half Hardy Annual
As above these seeds need a slightly longer growing period but as they are frost tender they will require sowing in pots or trays under protection and then when the danger of frosts has gone they can be planted in their final growing position.
HB - Hardy Biennial
Seeds are sown in spring or summer and the plants are moved to their flowering postition in autumn or the next spring, they will then flower 12 months after sowing.
HHP - Half Hardy Perennial
Seeds are sown early in the year in a propagator or heated greenhouse, they will then fly in the same year but will require lifing and storing in winter in a frost free place.
HP - Hardy Perennial
Sown early in the year and then plant out when the seedlings are large enough to handle, they should then produce flowers in the autumn.