> The best way to avoid bitter lettuces is to pick them at the right time. For crisphead types such as iceberg, butterheads (eg ‘Buttercrunch’) and cos, the central head should be firm. Don’t wait until your lettuce starts to flower or it won’t be worth eating.
> Harvest the leaves of leafy lettuces such as oakleaf every few days.
> Celery should also not be left in the garden too long or it becomes woody and bitter. And, as you do with leafy lettuces, rather than wait until the entire plant is mature, carefully remove just the outside stalks as you need them.
> Those in warmer regions may be harvesting early-crop potatoes this month. New potatoes don’t have thick skins so take care not to damage them with a shovel or fork. Hand harvesting is often best, loosening the soil first with a fork. Eat soon after harvest for best flavour. > If very few peas make it to the pot when harvesting, don’t worry. Eating them straight from the garden is the best way to teach children that their veges don’t come out of the freezer. Protein-rich peas are full of goodness but much of this is lost in cooking and freezing.
> When harvesting newly planted asparagus only pick spears that emerge in the first week or so, leaving the rest to turn into ferns that produce nutrients for next year’s crop. The following year you can pick for longer (2 weeks or so), and once plants have been in the ground for 3 years you can increase the cropping period to 8 weeks. Only cut back ferns when they have turned brown.