Gladiolus bulbs can be planted in the fall for spring blooms, or you can plant them in the springtime to ensure a summer bloom. Gladiolus bulbs should not be planted during very hot and dry weather, as they may wilt and die if exposed to too much heat and lack of moisture. If your bulb does get waterlogged (and it will!), try waiting until cooler weather before planting again. You’ll need between 1/2 an inch and 2 inches of soil at the base of each plant when planting gladioli bulbs.