Demystifying Those Peculiar Black Blobs on Tiger Lily Stems

Tiger lilies are admired for their large showy blooms in fiery shades of orange yellow, and red. But gardeners growing these popular perennials may notice some rather odd structures forming along the stems – tiny black bulb-shaped growths that appear between the leaves.

These mysterious black blobs often leave lily lovers scratching their heads in confusion, Are they some kind of disease or pest infestation? Or could they actually be seeds of some sort? Let’s dig into the details and get to the bottom of the identity of these perplexing black globules found on tiger lily stems,

What Are Those Dark Growths on Tiger Lily Stems?

The small, rounded black nodules frequently observed on tiger lily stems are formally known as bulbils. Bulbils are a specialized type of modified bud that contain rudimentary stem tissue, embryonic leaves, and the beginnings of a root system.

So while they appear foreign and strange these black bulbils are actually a natural part of the tiger lily’s growth cycle. They form in the junction where the leaf meets the stem called the leaf axil.

Tiger lilies are not the only plants capable of producing bulbils. Other true lilies like Asiatic hybrids and Oriental types can also generate these odd reproductive structures. Additionally, ornamental plants such as daffodils, garlic, onions, and some begonias are able to grow bulbils.

What is the Function of Bulbils on Tiger Lilies?

Bulbils act as a means of vegetative reproduction, allowing lilies to propagate clones of themselves asexually without the need for seeds.

In the wild, once the bulbils fully develop and swell to about the size of a pea, they will eventually detach and drop to the ground below. If conditions are favorable, the bulbils can then take root and grow into new genetically identical tiger lily plants.

So while they do not actually contain true seeds, bulbils essentially serve as miniature “starter bulbs” capable of giving rise to brand new lily plantlets!

When Do Tiger Lily Bulbils Appear?

Bulbils begin developing in early to mid summer. They start off green and tender, then progressively enlarge and turn darker in color as they mature over the summer into fall.

The bulbils reach their peak ripeness and maximum size just before the mother plant goes dormant for the winter. This coincides with when the bulbils naturally detach and drop from stems, allowing them to overwinter in the ground.

So in regions with cold winters, bulbils will be most abundant on tiger lily stems during late summer through early autumn.

Can You Propagate Tiger Lilies from Bulbils?

Absolutely! Those peculiar dark bulbils provide an easy, cost-effective way to propagate more tiger lilies without purchasing new bulbs.

Here are some tips for collecting and growing tiger lily bulbils:

• Wait until late summer/early fall when some bulbils have already started dropping. Gently twist and pull to harvest ripe bulbils still attached.

• Choose plump, rounded bulbils at least the size of peas. Avoid flat, mushy ones.

• Allow harvested bulbils to dry out for 1-2 weeks. Then store in a cool, dry spot over winter.

• In spring, plant bulbils 2 inches deep and 6 inches apart directly in the garden.

• Keep soil consistently moist but not waterlogged. Bulbils will sprout within a few weeks when soil sufficiently warms.

• Expect only small lily seedlings the first year. Bulbils take around 3 years to reach full mature flowering size.

• For quicker results, start collected bulbils in pots indoors the first year before transplanting outside.

Growing tiger lilies from the bulbils they freely produce is extremely rewarding! It provides free plants, preserves hardy heirloom varieties, and allows you to clone particularly stunning lily specimens.

Frequently Asked Questions About Tiger Lily Bulbils

For gardeners discovering bulbils on their tiger lily stems for the first time, some common questions may arise. Here are the answers to a few frequently asked questions:

Are the bulbils actual seeds?

No. Bulbils contain no embryonic plant. They act more like mini “bulbs” that can generate new cloned plants vegetatively.

Do you need both bulbils and seeds to get new lily plants?

No, just the bulbils alone. While seeds in pods are another way tiger lilies reproduce, they are not required for propagation from bulbils.

What causes bulbils to form – is it indicative of a disease?

Bulbils are completely normal and healthy. Removing them simply prevents self-sowing but does not harm the plant. Their presence is not a sign of any disease.

Should I remove bulbils to promote better flowering?

Maybe. Eliminating bulbils may redirect more energy to flower production. But it is unnecessary for the lily’s health and not guaranteed to increase blooms.

Can bulbils bloom the first year they are planted?

In very rare cases yes, but generally not until the 2nd or 3rd year. Bulbils need time to develop a mature root system and bulb before flowering.

Do all lily species and hybrids produce bulbils?

No. Through selective breeding some newer hybridized lily varieties have lost the ability to form bulbils. But most older heirloom types still readily generate them.

The Takeaway on Tiger Lily Bulbils

Those peculiar black blobs arising on tiger lily stems are not a cause for concern. Bulbils are simply an unusual form of vegetative reproduction commonly seen in these and other bulbs. While the bulbils may look odd, they are completely natural for tiger lilies to develop. The bulbils can be collected and used to easily propagate new cloned lily plants for free. Just wait for ripe bulbils to start dropping, harvest plump ones, plant them in soil, and let your new tiger lily plant babies grow!