Plant growth competition.

Much of the competition among garden plants takes place underground. In contrast to above ground competition which primarily involves a single resource, light, plants compete for a broad range of soil resources, including water and essential mineral nutrients in the soil. Below ground competition often reduces plant performance more than does above ground competition.

The above photo indicates the  primary importance in below ground competition is the occupation of soil space. The ability to occupy space depends on several root characters, including relative growth rate, biomass, fine root density, and total surface area.

Openings in the below ground root zone activity are likely to be important for plant establishment. The extent to which root gaps are associated with canopy openings and the role of root gaps in the dynamics of gap succession have only recently been researched.

Plant pests in Spring

Evidently, the day length has increased and we are experiencing higher temperatures. As a result, plants receive more sun light, based on the orientation of the garden bed, courtyard, balcony, etc., and new growth appears in the form of flower buds, stems and leaves.

Insects are cold-blooded animals, meaning that their body temperature is similar to that of their surroundings. They do not maintain a body temperature as do mammals and birds. Most insects do not develop or function well at temperatures below 10 C. This base temperature varies a few degrees up or down, depending on the insect species, but is near 10 C for most insects. When the temperature hangs between freezing (0 C) and 10 C, insects typically go into a dormant state in which body functions are greatly slowed down.

When temperatures are around 10 C for an extended period in the spring, plants continue to expand leaves and grow stems, and they can get ahead of their insect pests that are present but not developing. As a result, insect pest populations may be typical, but plant damage caused by those pests may be much less than normal.

Insect populations typically do not emerge at once. Some insects hatch from overwintering eggs or emerge from overwintering pupae early, and some of the same species emerge later.

The life cycle of plant pests becomes important as it provides gardeners with information on how to treat plant pests. As all insects hatch from eggs, they are short-lived and in some exceptions some insects can produce two or more generations per season e.g. aphids. Therefore, proper and timely identification of insects can assist in treating garden plants with greater success.

Happy Gardening!

Mealybugs

Jean De La Bruyere mentioned that "The first day one is a guest, the second a burden, and the third a pest".

The above mentioned quote relates to garden pests and in particular mealybugs.

Over the past year I have come across 3 cases of mealybugs effecting Daphne odora plants in various suburbs of Melbourne.

Mealybugs, depending on species, are oval, grey insects that grow up to 4mm in size.

Mealybugs grow in colonies; they are covered in wax and can easily be mistaken for fungi.

They thrive in warm, moist conditions, especially in protected places.

Given the previous comment and the weather conditions in Melbourne, of late, it does make sense that mealybugs appear at higher frequency.

The damage that mealybugs cause is wilting of growth and new leaves can be distorted.

Ants are the "transporters" of mealybugs and it is one of the first signs that gardeners need to be aware of.

If and when comes to chemical control, Malathion is recommended.

Principles of garden design for Poetry in Gardens

The following principles are engaged for the design of gardens by Poetry in Gardens:

•     Balance
•     Rhythm
•   Colour
•    Texture
•    Space

Balance

The concept of balance is based on the comfortable feeling of stability brought about by the way in which the area is divided up and the various visual weights are distributed throughout the garden area. 

Rhythm

In a visual design sense, movement is conveyed when the eye is led along from one area or point to the next. If this feeling of movement is repeated over and over then the design becomes more rhythmic. The elements which affect rhythm in major ways are line and form and to a lesser degree space, pattern, texture and colour.

Colour

Colour comes to us combined with every shape, size and texture and as a part of every material we use in the making of a garden. Colour has an amazingly potent impact on human emotions and thus becomes one of the best elements for creating particular moods and effects.

Texture

In garden design, textural concerns are more to do with the overall surface of whole plants rather than that of each leaf or petal. The overall texture of plants can play a significant role in setting the garden style.

A small quantity of string contrast in plant texture can be one tactic that helps give a garden real personality.

Space

Garden space can be characterised as static as there is no visual movement. A static space is one of the most contrasting elements that can be used in a garden, therefore the selection of plants will create a complementary aspect to the existing space based on the texture, colour, and rhythm as mentioned above.

In cases of large gardens, space allows plants to mature and appreciated in full size. Large shrubs and trees add character to large gardens by utilising space. 

Advantages of mulching

Mulches have various beneficial properties for plants, soil properties and gardens overall.

Among the advantages often contributed to mulches are the following:

·         Water conservation; mulching can greatly reduce soil evaporation and therefore reduce irrigation needs

·         Weed control; mulching can prevent weed growth and minimise competition with plants for water, light nutrients and space. Also, less time & labour will be required to follow up with weeding the garden.

·         Soil structure improvement; mulching reduces the impact of rain, run off and erosion. Organic and biodegradable mulches enrich soils with nutrients and plants grow healthier. The addition of mulches also reduces nutrient leaching and needs for plant fertilising.

·         Aesthetics; many mulch types such as wood chips, shredded bark and some types of crushed rock help present a neat, tidy, and finished appearance in landscape plantings and designs.

Drip irrigation advantages

Drip irrigation or low volume irrigation has several advantages, especially over the hot summer months.

In general, less water is used, reducing costs and conserving water resources.

Weed growth is suppressed because less soil surface is wetted.

Diseases associated with foliage will be reduced because foliage is not wetted.

Uniform application of water prevents plant stress and enhances new growth.

Importantly, water is placed where it is needed.

Temperature effects on plants

Plant species respond to high and low temperatures in different ways. The important aspect on effects is the combination of high or low temperatures and the length of exposure. During summer, a relationship exists between high temperatures and time of exposure. A generalisation is that higher temperatures require shorter exposure times before plants fail.

Soil temperatures and also lead to plant damage or plant death. The hot soil leads to death of cells at the soil line and is a particular problem with shallow root plants.

Planting the correct plant species at the proper time with respect to averages and extreme of temperature in each area will play an important role in the maintenance of high quality plants. The appearance of two identical plants can differ dramatically if they are grown at two different temperature and maintenance regimes.