Even the most diligent gardeners will have problems with their plants from time to time. Insects attack plants above and below the ground, leaves go yellow, roots shrivel, fruit is stunted (or doesn’t appear at all), and flowers drop before they have even opened. Sound familiar?
The first secret is to be forewarned so that you can identify plant problems before they do irreversible harm and kill the plant. The second is to know what to do to solve the problem.
Unfortunately diagnosing some plant problems can be extremely difficult. If a plant is diseased, you need to identify the correct disease. If insects are attacking, you need to fathom which insects are doing the damage. You can always try a broad-spectrum solution (whether it is organic or deadly poisonous), but some pests seem to be invincible. Then there are other factors including the quality of your soil, lack of water – or too much water, degree and intensity of sunlight and various other environmental factors.
So first let’s talk about what you need to look out for in order to indentify plant problems before they become deep-rooted and un-eradicable. Then we’ll talk about some of the vital environmental factors you need to worry about to avoid plant problems.
Signs and symptoms in leaves
If leaves are not perfectly formed and healthy, there is some sort of problem, particularly if they have spots, irregular mottling, if they become yellow or dry, or if they are stunted or appear distorted, in which case they may have some sort of disease. Discolored or spotted leaves, and leaves with mildew, are usually affected by some sort of fungus infection.
If leaves are attacked by insects, you will often see where they have been chomped or chewed, and you may even find the culprit on the leaves. Some insects literally take up residence on the plant, while others fly or crawl backwards and forwards, gradually increasing the damage day-by-day. Withered leaves and shoots may also indicate bugs, particularly sucking bugs, like awful aphids.
Some fruit plants are susceptible to both downy and powdery mildew. Downy mildew appears as pale, yellow, translucent, oily spots on the upper surface of leaves, with a downy white fungus forming on the underside of the leaves. It is worst in humid weather and most usually attacks grapes and some types of berries. Powdery mildew first appears on young leaves and the growing tips of plants, and then spreads to the rest of the plant. It often attacks apple, apricot, peach, pawpaw, mango and plum trees, as well as grapevines.
Signs and symptoms in roots
Recognizing plant problems in roots is not nearly as easy as it is to see problems that are openly displayed on leaves. But if a plant simply starts wilting and dying, for no apparent reason, and the leaves and stem look otherwise normal, it could very well be due to some sort of root damage – possibly too much or even too little water, or an invasion of insects or other pests below the ground.
Signs and symptoms in fruit
To ripen properly, fruit needs sunlight and it should be reasonably sheltered otherwise it will be effected by the wind. For example, hot seering wind will cause young fruits to drop.
Sometimes, when summer is very hot or the winter has been milder than usual, some kinds of fruit suffer from what is called delayed foliation (which is the process of producing leaves). The symptoms of delayed foliation are that the tree will flower for much longer than usual without the fruit appearing. Often when the buds appear, they open slowly and die. Any fruit that does appear is then usually of a poor quality.
Often fruit is “stung” by insects, or worms actually burrow into the fruit. But when fruit trees and other fruit-bearing plants are attacked by insects, it isn’t only the fruit you need to worry about. Ants, aphids, fruit flies and various moths and slugs attack these plants often doing so much damage that the plants doesn’t ever produce fruit.
Other factors to consider
Sometimes you will find that plants have been damaged, not by insects or disease, but by carelessness. For example if you aren’t prudent with your lawn mower or weed trimmer, these invaluable tools can bruise and break stems, roots and the leaves of plants.
When it suddenly gets very hot or very cold, plants may also be adversely affected. In extreme cold, foliage is likely to die off, while in the heat, leaves are often scorched by the sun. In high heat, they often go yellow and might drop. While we can’t control drought and harsh frost conditions, we can take steps to minimize their effects.
When gardens are flooded because of excessive rain, roots often become waterlogged, particularly if there is inadequate drainage, or there is a lot of clay in the soil. If there is too much water in the soil there often won’t be enough oxygen for the plant to survive, and it will simply wilt and die. Or the leaves may go yellow as they do when there is too much heat. But remember that different plants have different needs in terms of sun, rain and soil quality, and some are a lot more hardy than others, so you need to take individual preference into account as well.
The quality of the soil in your garden is another important factor. If there aren’t sufficient nutrients in the soil – and the right nutrients for the plants you are growing – this too might cause yellowing and stunted growth. The essential nutrients needed for healthy plant growth are:
- The macro elements – nitrogen, phosphorous and potassium, along with calcium, magnesium and sulfur.
- Trace (or micro) elements including boron, copper, iron, manganese, molybdenum and zinc, which are required in minute quantities.