Pears (Pyrus communis) have similar needs to apples but flower a week or two earlier and are more sensitive to spring frost, so give them a warm, sheltered position in full sun and deep, fertile soil with pH 6.0–7.0. Plant bare-root trees from late October to March; quince rootstocks keep trees compact and bring them into cropping sooner, but need good soil and permanent staking. Most varieties need another pear flowering at the same time for pollination. Prune in winter to thin the crown and remove vigorous upright water shoots. The main diseases are pear scab and pear rust, which shows as orange spots on the leaves and spreads from nearby junipers; in warmer areas fireblight is also a serious threat, and blackened shoot tips must be cut out well below the damage. Pick early varieties in August while still firm, as they turn mealy on the tree. Winter varieties such as 'Conference' or 'Alexander Lucas' are picked in October and ripen in store over several weeks.