The Dutch Irises (x hollandica as their name gives them away), or bulbous irises, have an underground storage organ in the form of a bulb rather than a rhizome like their arguably more famous cousins - the Iris germanica.
The Dutch irises are also not, it is important to note, natively Dutch. They are a result of careful breeding between two main botanical species: Iris filifolia (which is sometimes confused with the similar Iris xyphium), both native to Spain and North Africa, and Iris tingitana, from Tangier and northern Morocco.
This allows the hybrids to be highly tolerant of periods of drought and of scorching sun.
And for those who are wondering what on earth is the difference between petal/sepal/tepal > To explain, normally on plants we see colourful petal sheld within a familiar green bud of outer things called sepals. Sepals are tougher, protecting the more fragile inner petals. However, on some plants, the sepals and petals have no difference and these are jointly called tepals.
That's all for now!
Floral Morphology
Each flower is composed of six tepals arranged in two whorls.
The three outer tepals, known as falls, are broader and spatulate in shape, while the three inner tepals, known as standards, are narrower and held more upright.
The tepals are typically lilac to bluish-purple in color, with darker contrasting veins and a central yellow stripe or signal on the outer tepals.
The flowers measure approximately 5 to 8 centimeters in diameter and are slightly fragrant.
Each flower also bears three petaloid style branches that arch over the stamens, a characteristic feature of the iris genus.
Reproductive Biology
The Apollo cultivar forms over time a very narrow, upright clump of 50 cm when in flower, and spreads without theoretical limit through the production of bulblets.
Sexual reproduction occurs when pollinators, such as bees, visit the flowers and transfer pollen from the anthers to the stigmas.
After fertilization, the plant forms seed capsules containing several seeds, although seed production may be irregular in colder climates.
Vegetative reproduction occurs as the main bulb produces bulblets - little bulbs with the same genetic information, allowing the plant to form larger clumps over time.
This mode of reproduction ensures the long-term persistence of the plant in dry environments and enables gardeners to propagate it easily by division.