How to grow Iris


July through September (late summer) is also a good time to dig and reset clumps of iris that are crowded, usually after 3-4 years growth. If you live in an area with a harsh winter climate, your iris may require some sort of winter protection, especially the first year. Iris will thrive without feeding but will respond to fertilization with spectacular results. An application of a well-balanced fertilizer (5-10-5), applied as a top dressing dusted around and in between plants in the early Spring and very late Fall is desirable. Fertilizer can also be applied right after bloom is finished. Any fertilizer application should be light. In general, fertilizers high in nitrogen, including fresh manure, should be avoided because too much nitrogen encourages rot problems. Every 3 or 4 years, dig clumps, remove and discard the old center divisions that have bloomed and replant the new large fans with strong foliage. Use a sharp knife to separate rhizomes, borer holes or diseased looking parts. Trim leaves halfway back to an inverted V shape (^) and also trim roots back to about 4-6 inches. Soak for 1-10 minutes in 10% bleach solution, dry in cool, shady place for a day. If leaf spot is a problem, soak in fungicide for 30 minutes after rinsing in bleach water. Dust any open wounds with sulfur

Growing Iris from seed

About two months after pollination a seed pod will turn brown and split open. Harvest the golden brown seed and allow them to dry out for a couple more months (Be sure to keep the record of the parents with the seed). In late October plant the seed about 3/4" deep and 1" apart in well drained soil. The planted seed should spend the winter outdoors. The following spring little Iris plants will grow from the seed you planted. Replant and space out the “baby” Iris when they become crowded.

Try to aim for a seed spacing of at least 1.19 inches (3.05 cm) and sow at a depth of around 0.99 inches (2.55 cm).

Transplanting Iris

Iris thrive in a well-drained neutral to slightly alkaline soil, but is generally tolerant of most garden soils. At least six hours of sun are needed for vigorous growth and flowering. The preferred time for planting is in the late summer-fall to give the roots time to develop over the winter and store up nourishment to support spring blooming. Good air circulation is essential; without it, foliage diseases and rhizome rots thrive. It is important when planting the rhizomes to cover them with no more than one inch or less of soil. However, the rhizome should rest upon well-cultivated soil deep enough to allow the roots room to develop and spread. Water the new plants thoroughly, but wait until early spring to add fertilizer. * Build up a small mound of soil in the center of the planting hole. * Center the rhizome on the soil mound and spread out the roots on either side. “: * Firm the soil around the roots. Newly planted rhizomes should be watered thoroughly.”:

Ensure that temperatures are mild and all chance of frost has passed before planting out, as Iris is a very hardy plant.

Harvesting Iris


How long does Iris take to grow?

These estimates for how long Iris takes to sprout, grow and harvest are from real observations from real gardeners, right around the world.

Days to Germination How long does it take Iris to germinate?
19 days

Average 19 days | Min 7 days | Max 301 days (3)

Days to Transplant How long until I can plant out Iris?
+ days

Average days | Min days | Max days (0)

Days to Maturity How long until Iris is ready for harvest / bloom?
+ 85 days

Average 85 days | Min 7 days | Max 1475 days (22)

Total Growing Days How long does it take to grow Iris?
= days

Iris Etymology

Iris takes its name from the Greek word for a rainbow, referring to the wide variety of flower colors found among the many species

Iris Folklore & Trivia

In some languages, irises are called flags or sword flags, relating them to symbols of heraldry and royalty, hence the original “Fleur de lys” of heraldry. In Japan the shape is seen to express heroism and the blue colour refers to blue blood, so irises play a key role in their spring festival for boys.

Other names for Iris


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