Dandelion vortexes

Surprisingly, dandelion seeds use a method of flight previously thought impossible.

Abstract
Wind-dispersed plants have evolved ingenious ways to lift their seeds1,2. The common dandelion uses a bundle of drag-enhancing bristles (the pappus) that helps to keep their seeds aloft. This passive flight mechanism is highly effective, enabling seed dispersal over formidable distances3,4; however, the physics underpinning pappus-mediated flight remains unresolved. Here we visualized the flow around dandelion seeds, uncovering an extraordinary type of vortex. This vortex is a ring of recirculating fluid, which is detached owing to the flow passing through the pappus. We hypothesized that the circular disk-like geometry and the porosity of the pappus are the key design features that enable the formation of the separated vortex ring. The porosity gradient was surveyed using microfabricated disks, and a disk with a similar porosity was found to be able to recapitulate the flow behaviour of the pappus. The porosity of the dandelion pappus appears to be tuned precisely to stabilize the vortex, while maximizing aerodynamic loading and minimizing material requirements. The discovery of the separated vortex ring provides evidence of the existence of a new class of fluid behaviour around fluid-immersed bodies that may underlie locomotion, weight reduction and particle retention in biological and manmade structures.

Dandelion seeds fly using ‘impossible’ method never before seen in nature
Nature, Revealed: the extraordinary flight of the dandelion
Paper, A separated vortex ring underlies the flight of the dandelion
Research Gate project, The form and function of the dandelion fruit

Dandelion pollen
2018 PhotoMicrography Competition
Dandelion fiber
2018 PhotoMicrography Competition

Vanilla planifolia

Vanilla cuttings getting started outside[/caption]

I’ve grown this off and on for years and have yet to manage a single flower. As a vine it is easy to grow.

Grow in dappled shade to shade, burns easily in direct sunlight. Keep planting medium moist, loves high humidity.

Propagate from stem cuttings

Warm climate orchid 65’F minimum – 85’F. I keep it outside in the summer where it handles temperatures as high as 100’F. In the winters I bring it in and curl up the vine inside large terrariums

Native to Mexico, West Indies, Cuba where it grows wild in forests

Why One Island Grows 80% of the World’s Vanilla

Kew Science, Vanilla planifolia

Button Bush (Cephalanthus occidentalis)

This is a deciduous shrub in zone 5 through 10. It blooms early summer with fragrant white spherical flowers. I’ve only seen it at the edge of wetlands growing wild.

The branches were used by Native Americans in arrows and stick games

Leaves contain glucosides, may cause skin rashes, severe toxin if ingested – keep from humans and pets

Sun to part shade
5′-15′ tall
4′-8′ spread
prefers wet soil, wetlands
Attracts butterflies, bees and hummingbirds

Easily grown from stem cuttings, challenging to grow from seed

Native to US

Propagation by seed

Many plants are easily grown from purchased or collected seeds.

Planting depth is related to seed size, the general rule of thumb is to plant it so the soil on top is about equal to the size of the seed.

Some seeds are placed on top of soil instead of being buried, they need light to germinate.

Planting time is usually spring or fall. Some seeds need a cold spell before germinating, cold stratification. This is typical of perennial plants that go dormant over the winter. After 6-8 weeks of cold ( in the ground or in your refrigerator ) plant them. Seeds that require a cold stratification usually won’t germinate until it is warm and moist after the cold spell.

Seeds from annuals that die off in the cold are typically planted once the ground warms up. If you are trying to get a jump start on spring a warm window, radiator or electric skillet can be used to warm the bottom of the pots.

Hard, thick seeds such as those in the legume family may need to be scratched or nicked (scarification) before germinating. Large nurseries use chemicals, hydrogen peroxide or sulfuric acid, to scar the seeds. The reason for nicking the hard shell is to let in some moisture to kick start germination

Seeds that are inside a fruit, tomatoes, citrus fruits…., need to be removed from the fruit and dried before planting. I remove the fruit and spread the seeds on a paper towel for a couple of days to dry them.

Most seeds can be stored for years if kept dry and at temperatures ~40’F-60’F

Fungus is a common problem when starting seeds in pots or indoors. Spraying with water usually kills off the fungus. More serious cases can be treated with copper ( available at most garden supply stores )

I find starting slow growing perennials, like carnivorous plants, work best in small terrariums where they’ll be humid and safe from damage. I use peat moss as the medium. Many take ~4 years to reach 3″ across.

Test tube plants are growing in popularity. I haven’t had any success starting them myself, but I frequently purchase plants started in test tubes. You can find agar and test tubes online. The trick is to sterilize the tubes, mix and seeds with out killing the seeds.

I’ve also seen seeds started in test tubes half filled with water. Mine molded, I’ll try again when it’s too cold to go outside and putter in the garden.

Seed Germination Database
Seeds and Seedpods Database
Seeing the light: Scientists unlock seed germination process

Sedum morganianum Burrito aka Donkey Tail

New cuttings potted up mid April 2018
Early Aug, the growth rate is increasing, once the weather cools a bit it’ll grow faster

First listed by Glasshouse Works in 1988, it’s a species native to eastern Mexico. It’s a smaller, thicker version of Sedum edeveria.

It’s most common use by gardeners is in hanging baskets.

Protect from cold, it prefers temperatures ~ 70’F, anything lower than 45’F will damage or kill plant

Sun to light shade, minimum 4 hours of direct sun daily

Keep damp in growing season, drier in winter

Lightly fertilize

Dropped leaves or yellowing leaves appear if the plant isn’t getting enough light

Tiny red flowers will appear on end of tails

Propagation by cuttings or leaves placed in damp soil and moderate sun. As new growth appears gently cut back on watering and give the plant more sun.