Planting Gladiolus in New Zealand
1. When to Plant
Timing: Plant your Gladiolus corms in spring, from September through to November.
Frost: Wait until the danger of the last frost has passed in your area.
Pro-Tip: For a continuous display of flowers through summer, plant a new batch of corms every 2-3 weeks during this spring planting window.
2. Choosing and Preparing the Location
Sunlight: Gladioli thrive in full sun. Choose a spot that gets at least 6 hours of direct sunlight per day.
Soil: They require well-drained soil. If you have heavy clay, improve drainage by mixing in compost and a bit of sand before planting. This prevents the corms from rotting.
3. How to Plant the Corms
Depth: Dig holes or a trench about 10-15 cm deep. Planting them on the deeper side helps anchor the tall flower spikes.
Orientation: Place the corm in the hole with the pointed side facing upwards. The flatter, slightly concave side is the base where the roots will grow.
Spacing: Space the corms 10-15 cm apart to give them enough room to grow.
Watering: After planting, cover them with soil and water them well to settle them in.
4. Care During the Growing Season
Watering: Keep the soil consistently moist, especially during dry spells in summer and when you see the flower spikes starting to emerge.
Support: Gladioli grow tall (often over 1 metre) and can be knocked over by wind. It's a good idea to place stakes near the corms when you plant them or be prepared to add support as the flower stalks grow.
Flowering: You can expect beautiful blooms in mid to late summer, typically about 90 to 100 days after planting.
5. After Flowering (End of Season Care)
Lifting Corms: In most parts of New Zealand, it's best to lift the corms for winter storage. In autumn, after the flowers have faded and the leaves have turned yellow and died back, carefully dig up the corms.
Storing: Brush off the soil and let them dry in a warm, airy place for a week or two. Then, store them in a cool, dark, and dry location (like in a paper bag or onion sack in a garage) until you're ready to replant them the following spring.
