My Poinsettia plant from last year is lush and beautiful. How do I get it to flower for the holidays? I read something about keeping it in the dark. Would covering it with a black plastic bag do it?
For flowers to form, Poinsettias need short days and long nights. It's the day length that triggers the blossoms.
In addition, the showy part of the Poinsettia is not the flower but modified leaves called bracts. It's the bracts that turn from green to red or another color. The actual flower is the small yellow-green, round structure in the center of the bracts.
The color change doesn't occur naturally in our area because of the abundance of indoor and outdoor light sources such as street lights, security or motion sensors, and household lights.
So, covering the plant(s) to get them to bloom is valid. The most challenging part of this is the repetitiveness.
Starting now or the first week in October, cover the plants at dinnertime and remove them at breakfast. When flowering begins, the green leaves will fade to a maroon color.
Once you see this, you can stop covering the plant(s), as the bracts will continue to color up without any additional help.
You can cover the plant(s) with a black plastic bag, but I prefer a ridged-sided box as you can quickly cover and remove it.
The other advantage of a box is it prevents unintentional breakage and bruising. So no light can get in the box, tape the bottom edges of the box and be sure the plant(s) are sitting on a flat surface.
Another option is to invert a tomato cage, place it over the plant, and then use a black plastic bag for covering.
Your plant should be in bloom as early as Thanksgiving or shortly after that.
How do I go about planting and caring for Bearded Iris? Is now a good time to plant?
Fall is an excellent time to plant Bearded Iris.
They like sunny, well-drained soil, so they incorporate generous amounts of soil amendments, homemade compost, and a starter fertilizer.
Next, you must level the area and plant the new Irises so three-quarters of the rhizome is above the soil surface. If they're planted too deep, they will rot. Also, be sure the fan of leaves is facing the sun.
Bearded Irises are water-wise; be careful not to over-water them during the summer and Fall.
You remove the spent flowers on a dry day so the soft tissue will callous over quickly. Do not trim the foliage off with established plants except to remove the areas with leaf spots.
Only when the leaves turn brown in the Fall should they be cut back or pulled off, and the clumps can be divided as early as August. You feed them twice yearly, spring and Fall, with an organic fertilizer.
And finally, keep litter and grass away from the Iris plants because clean cultivation is the best precaution against future troubles.