Is it necessary to drill holes in the bottom of containers for drainage? I've purchased several inexpensive plastic pots that have no drainage holes. If I don't overwater them, won't the plants suck up the water leaving none to stagnate at the bottom? What is good to plant for color for the winter months?
NO drainage holes may work, but it will be tricky to gauge when to add more water. The amount will vary significantly between the seasons.
Another issue will be the depth of the container. Your new plants may not use all the excess water. You then have an issue with uneven soil moisture.
The lower half could stay very wet while the top half is dry. It isn't easy to water just the top.
A shallow container would be easier to water than a deep one.
This is not going to work with outdoor containers during the rainy season.
To me, this whole idea is a lot of hassle. A better option would be to purchase another pot with drainage holes that will fit inside the current ones.
It's a pot within a pot. The excess water can be easily dumped or drill holes in the existing pots.
For seasonal color, Cyclamen, Primroses, Primulas, Pansies, Violas, Calendulas, or Iceland Poppies are available for planting.
Planted now these plants will bloom right into next spring. Also available are Mums, Snapdragons, Flowering Kale, and Cabbage, but I'd look to replace them on or before the first of the year.
Cyclamen mixed with Violas or Primulas are a lovely combination. They can be grown in any location that gets lots of light. Sun or shade isn't essential during the winter months.
The growth should be minimal, so plant them close to one another; otherwise, the containers will look sparse.
And finally, you need to add a starter or all-purpose fertilizer at the time of planting so they don't turn yellow from being hungry.
The leaves of my Dahlias are full of Mildew; however, the flowers are not affected. What can be done now to prevent this?
There are many products available for Mildew control on Dahlias and many other plants. But I would not be inclined to apply anything this late in the season.
Dahlias will be going dormant soon, and the beginning of the rainy season is not that far off.
Mildew is an airborne disease that's a problem when moisture remains on the foliage after the sun goes down.
Once the rainy season concludes, the marine influence is a significant contributor to Mildew as well as watering in the early evening.
To combat this problem, I'd apply Bayer Advanced All In One Rose and Flower Care. It's a granular or liquid solution that's applied to the roots, so no spraying is necessary, and it gives you six weeks of protection.
Besides controlling Mildew along with other diseases, it fertilizes and controls many sucking insects such as Aphids.
I'd make my first application in late May or early June.