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Growing Guide: How to Grow Gladiolus

Growing Guide: How to Grow Gladiolus

Gladiolus, also known as Sword Lily, is a stunning perennial flower that blooms in the summer. The name is actually derived from the Latin word for sword, ‘gladius’. The many varieties of Gladioli come in all sorts of colours, bright and soft. You’ll find them with single colour, bi-colour, and even tri-colour petals. They look amazing planted in groups, and will definitely impress in any garden.

WHEN
Plant in spring
Bloom in Summer

Full Sun
Well-draining soil

WATER
Water regularly if there’s no rain

WIDTH & DEPTH
15 cm apart
10 cm deep

Arrival

When your DutchGrown Gladioli arrive and you can’t plant them immediately, it’s important to store them correctly: unpack them right away and put them in a dry place with plenty of air circulation.

Garden & Container Planting

Gladiolus bulbs bloom in the summer, and can be planted throughout the season from spring to early summer. If you’re going for large quantities, you can stagger your planting over time so that you can enjoy their blooming throughout the whole summer. To thrive, they need to be planted in a spot with full sun, in rich and well-draining soil. A layer of mulch will help keep the soil moist. Plant the bulbs approximately 15 cm apart, and 10 cm deep. Plant them upright, with the pointy side up and flat rounded side down, to give them the right head start to a successful bloom. Keep them well watered, especially in the absence of rain, ensuring they get the equivalent of 2.5 cm of rainfall per week.

Expect to see your flowers bloom in about 90 days from when the foliage begins to emerge overground. The tall stems are fairly strong, with sword shaped leaves. The flowers are funnel shaped with open, ruffled petals, and each flower spike can bloom with up to 20 florets. These blossoms open up one by one, starting from the bottom and working their way up to the top of the stem, so each flower will give you full colour blooms for around two weeks. As they are such large flowers, they can sometimes become a bit top heavy. To prevent them from leaning, you can support them with bamboo canes, by tying them onto the canes gently to secure them. You can do the same with a larger area by using more bamboo canes and encircling the section. Alternatively, use them as cut flowers! To do so, you would cut the flower before it fully blooms, while the top florets have still not opened. This way, you are avoiding the leaning and heaviness altogether. Make sure to cut off the top bud as well, to slow down the rest of the buds from opening and get a lengthier bloom.

After they have finished flowering, remove the spent stalks and let the plant wither naturally. Once the plant has turned brown, cut it down to ground level, and it should come back again the following year.

How to plant Gladiolus in your garden:

  1. Start with loose, rich soil and a layer of compost, in a spot that gets full sun.
  2. Plant the Gladiolus bulbs about 10 cm deep and 15 cm apart, pointy side up.
  3. Water regularly: provide the equivalent of 2.5 cm of rain per week in dry weather.
  4. After the Gladioli have bloomed don’t cut off the foliage. Leave it until it’s completely withered and yellow, then remove.

How to plant Gladiolus in containers:

  1. Start with large, deep containers filled with multipurpose compost.
  2. Place the gladiolus bulbs on top, about 7.5 cm apart, and cover with more compost.
  3. Add a layer of gravel to finish off and keep weeds away.
  4. Stagger your planting in monthly intervals to enjoy a succession of blooms throughout autumn.
  5. After flowering, keep the bulbs in the containers throughout winter in a sheltered area, so they can bloom again next season.
Meet Ben, our Flower Bulb Specialist
Meet Ben, our Flower Bulb Specialist

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