1. Planting at the wrong time of year
What this means will vary from place to place. While in some charmed places most things can be planted year-around, the majority of locales have definite planting seasons. For instance, in many areas of the West or Southwest, fall is considered the best time to plant most shrubs, trees, groundcover, and lawns.
This timing issue also comes into play with annual flowers and vegetables. Some flowers and vegetables like the warmth of the spring and summer, while others prefer the coolness of the fall and winter. The goal is to time your planting for the earliest part of the season you are planting for; but not too early.
Let’s use marigolds (a summer annual) for an example. The plant likes heat, but can freeze if the temperatures are too cold. In some areas, you might begin seeing marigolds for sale in the late winter.
Can you plant them then? Of course. Should you? Maybe not. Why? While it might work—if temperatures don’t drop too low—you could be replacing your plants if they do.
If you are not sure whether to plant something at a certain time, please ask us; we will tell you whether it’s the best time or if you would be better off waiting. Many garden centers serve a fairly large geographical area and these areas oftentimes have differing microclimates. That is why you will sometimes see plants in your local garden center that may be out of season for your particular area. The other thing to keep in mind is not to plant too late. Planting too late will not allow your flower or vegetable to achieve maturity before the cold (or warm) weather comes and stops it in its tracks!
2. Planting in the wrong exposure
While some plants will take any exposure, most prefer predominantly sun or mostly shade. When you are shopping for your plant, take notice of where the plant is situated in the garden center; this will give you a good idea of where it will be the happiest in your garden. If you’re not sure, ask.
3. Planting in the wrong zone
Just because you see a pretty plant growing in the sun, does not necessarily mean it will grow in the sun in your garden. Some plants prefer hot, dry areas and some prefer cool, misty spots. This is where the USDA Climate Zone chart or the Sunset Western Garden Climate Zone chart will help. Most plants sold in garden centers are marked with their appropriate climate zone or if they are not, the garden center team can tell you if it will grow in your zone.
4. Planting plants with different requirements near each other
Some plants prefer dry, well-drained soil and others like more water. Don’t make the mistake of thinking that you will be able to manage the two effectively when they are planted next to each other—you won’t. Save yourself the angst and use plants with similar needs together. The plants will be happier— and so will you.
5. Watering too often, too much, not enough, or not deep enough
Whew! The above may seem like a contradiction, but what we’re trying to say is that plants have different watering needs and soils (because of their differing compositions) respond to water differently.
The most common mistake in regard to water is not watering enough (in terms of frequency) and not watering long enough (in terms of volume). A small plant can dry out quickly, especially in warm weather. When first planted, it should be regularly monitored to observe its water needs. Also, you need to leave the water on long enough to saturate the entire root-ball of the plant (for some things, this might be longer than you think). Standing over the plant and giving it a quick shower with your hose will probably not be enough. Also, deeper watering encourages roots to go down, thus increasing the plant’s drought tolerance.
On the other side of the coin is the gardener who is so dedicated that he/she waters constantly. This is not good either. Watering too often or too much water volume (especially in heavy soils) can cause disease; eventually, the roots of the plant will rot. So, strive for vigilance but not obsession when applying water to the garden.