Grasses' Pests And Diseases

Among all the ornamental plants grown in the garden, the grasses are known to be the most resilient against diseases and pests. In fact, they are the most pest-free and disease-free plants. It is said that provided you select the right kind of ornamental grasses and plant them in the appropriate location in your garden, they are usually free from diseases as well as insects. Although, a number of ornamental grass species are more susceptible to problems in comparison to other varieties, majority of the grasses are easy to cultivate and they also demand very little care and attention.

Miscanthus mealy bug

Although Miscanthus mealy bug is a treacherous pest, luckily it seems to be confined to the genus Miscanthus. In effect, this bug, Miscanthicoccus miscanthi is indigenous to Asia. It is significant to note that without any aid, the mealy bug does not have the ability to travel long expanses. Precisely speaking, possibly this bug is unable to move in excess of just a few feet by itself. However, the dispersal of the mealy bug has actually been unsuspectingly, by means of selling as well as exchanging the plants infested with this insect. Generally, it is difficult to detect the presence of this dangerous pest. It only becomes conspicuous when the population of this bug reaches a very high number on any individual plant and the symptoms of infestation on the surface become easily visible.

Usually, the mealy bug is capable of growing to a maximum length of 4 mm (3/16 inch) and it thrives in the narrow gap between stem and the enfolding leaf sheath. Initially, this pest generally forms colonies near the base of the plant and gradually ascends upward with the amplification of their population. As mentioned above, mealy bugs are almost invisible till they are full grown and attain a noticeable size. In order to ascertain whether your plant has been infested with mealy bugs, the best thing you may do is to take a lower leaf sheath from the stem of the plant and check it. You will notice syrupy honeydew and a white colored powdered wax formed by the mealy bugs to help the pests to conceal their presence.

In general, the initial surface symptoms of a plant being infested by Miscanthus mealy bug include slowing down of the plant's growth and an abnormal entwining of the flowering head. In addition, the color of the sheath tissue as well as the stem becomes deep red in parts where the mealy bugs are drawing their food from the plant, particularly in the later part of the growing season. Even when a plant is severely plagued, it is not eliminated, but is decreased to ugly, distorted masses as the white powdery wax swathes its stems, particularly in the lower parts. Plants that are infested by this bug usually become incapable of flowering in any way. In some cases, the flowering stalks may possibly be underdeveloped resulting in the flowers to open droopingly among the foliage, instead of blossoming elegantly above.


Aphids, also known as plant lice, when they materialize, may be horrid. However, generally they will not result in any grave harm to the plants. Aphids may be restricted by supplying attenuated soap water (using one tablespoon of dish washing detergent to one gallon of water). Alternately, they may also be gotten rid of by using a forceful water spray using a hose.

Snails and slugs

It may be noted that snails and slugs are more dangerous to the plants compared to the insects for they can cause more harm to your ornamental grasses. As snails and slugs do not have any effect on the majority of the ornamental grasses, they do not require any special treatment. However, sedges, grasses having juicy leaves as well as sub-tropical grasses are extremely vulnerable to the harm caused by snails and slugs. It is worth mentioning here that a shred of copper strip or soils enclosing diatoms or their fossil remnants (diatomaceous) is effective in putting off slugs. Collect the slugs at night time and drop them in soapy water; start beer ensnares or shower salt water over them to eliminate them.

Slugs are basically insatiable eaters and may possibly obliterate grass or even clover seedlings. The harm caused by slugs is irregular. A clear indication of any attack by slugs is the gooey trace left behind by them. As slugs are nocturnal beings, you can detect their existence if you visit your garden or field after dusk with a torch. We all know that prevention is always better than cure and, hence, all efforts ought to be made to put off the slugs from attacking your plants. In order to do this, you need to prepare a solid seedbed devoid of any crack, clods or crevices - places where the slugs may lie in wait. When the slugs are put out in the open on the surface of the soil giving no place to conceal them, they soon become preys to birds as well as other animals, which just shrivel them. Alternately, you may also use chemicals to control the attack of slugs. In this case you are opting to use chemicals to get rid of slugs; you will find several patented products in the market which are prepared from methaldehyde or methiocarb.


While the larvae of sitona weevil (a type of beetle) invade the root system of fully grown red and white clover plants, the adult weevils attack the seedlings and the leaves of the established plants. The adult weevils that are as big as a match head are able to forage the seedlings reducing them to the size of stubs. Unfortunately, till date there are no approved methods especially to restrict the sitona from attacking the clover seedling by application of chemicals. Nevertheless, it has been found that applying chlorpyrifos, for instance Dursban 4, which is used to restrict leatherjackets or fruit fly in grass seedlings accompanying them, are useful in controlling the weevils.


Gardeners growing ornamental grasses usually find that gophers (a type of ground squirrel belonging to the genus Citellus) to be the biggest threat to their plants. Even the presence of a solitary gopher in your garden can lead to wanton destruction with the grass planting. In fact, gophers have a propensity to consume the roots exactly at the base of the grasses, frequently grazing them to the ground level. It is advisable that if the places where you are growing ornamental grasses have an acute invasion of gophers, you make use of wire baskets to keep them away from accessing the crown of the plants. You may put the ornamental grasses in big baskets made from chicken wire or a small net. It is worth mentioning here that specific grass species may be appetizing to gophers as well as voles (small rodents belonging to genus Micotus). You may make use of the regular methods to control these pests - cultivate the ornamental grasses in baskets that are gopher proof. Alternately, you may grow the grass species which are not palatable to the gophers.


People growing ornamental grasses often find rabbits to be a major problem. In fact, the rabbits treat specific ornamental grasses like afters or desserts. Habitually, rabbits never trouble grasses having sinewy, delicately textured or sharp-edged leaves. Provided they find natural food in the vicinity, rabbits generally keep off ornamental grasses. However, if rabbits are proving to be a nuisance for your plants, it is advisable that you erect a fence to keep them away from your garden.


Deer are seldom considered to be a nuisance for grasses. However, they do nonchalantly leaf through the juicy new growths occasionally. But when the grass has become firm, the deer will never touch them again.

In general, deer has a propensity to try out all new plants in your garden at least once, if not again. More often than not, deer loathe the plants whose leaves have sharp edges and, therefore, will not touch this type of grass. In places where deer is really a major problem, it is advisable that you continue growing grasses having razor-sharp leaves and also think about erecting a fence to keep off deer from your garden.


Rust is basically an infection caused to plants by fungus and it appears on ornamental plants in the form of orange spots. Such orange spots may extend to different parts of the plant, especially covering its leaves. When your plant is plagued with rust, get rid of the infected leaves immediately when you notice orange spots on them. And when the growing season of the grasses end, get rid of all the infected plants and eliminate them with a view to stop this fungal disease from spreading. In case the ornamental grasses you planted in the previous season were plagued by rust, it is important that you thwart them from returning by applying wet table sulfur at regular intervals beginning quite a few weeks prior to the time when the disease normally invades the plants.

When specific types of grasses are not appropriately spaced during plantation, they may become susceptible to foliar rust disease. The same may occur if the grasses are being grown in excessive shade. Adequate exposure to sunlight as well as appropriate spacing of grasses will diminish the risks of them being plagued by rust.

Ornamental grasses
The families of grasses
How grasses grow
The life of grasses
Growing ornamental grasses
Growing grasses in containers
Propagating ornamental grasses
Maintaining ornamental grasses