Direct Seeding
Direct seeding for revegetation
'Direct seeding' means applying seed directly to the site where plants are wanted.
'Direct seeding' means applying seed directly to the site where plants are wanted.
- Direct seeding at a glance
- Advantages
- Disadvantages
- Critical factors
- Methods
- Direct seeding references (33KB pdf) [Expired]
- Advantages of direct seeding
- Disadvantages of direct seeding
- Critical factors for direct seeding
- Climatic conditions
- Choosing the correct species for the site, region and purpose
- Obtaining viable seed and treating if necessary
- Preparation of a good seed bed
- Controlling weeds
- Sowing at the right time
- Sowing at the right depth
- Direct seeding methods
- Areas can be revegetated quickly and cheaply
- Seeds cost less than seedlings
- Seed is easier and cheaper to transport and store than seedlings
- Seeding requires less time and labour than seedlings
- A mixture of trees, shrubs and groundcovers can be sown at the same time. The different rates of germination mimics natural regeneration
- The mixture of tall, medium and small species can make a more effective windbreak
- Direct seeded plants tend to have better root growth and are therefore more prepared for climatic extremes
- More plants may germinate in the years following sowing
- On farm machinery can be used to prepare seed beds. This removes the need to use specialised seeders.
- Less reliable establishment than for seedlings on some sites and across seasons. Not as suited as seedlings to deep, non-wetting sands or heavy textured soils
- There is a requirement of some species for a special seed treatment before sowing
- There is a low survival rate of viable seed
- When a mixture of species are sown, there are limits to the number of herbicides that can be used for weed control
- It often takes 9 to 12 months to properly see the results of a direct seeding project, with additional plants sometimes geminating in the second season.
- Favourable rainfall is very critical for direct seeding success
- The areas best suited to direct seeding have a reliable, moderate to high rainfall without extremes of temperature
- Successes in low rainfall zones have generally been in the above average rainfall years. Time of sowing, site preparation, weed control and species selection is critical for success in low rainfall areas.
- In general, plants which grow naturally in the same conditions have the greatest chance of success
- Using a variety of species allows for differences in germination rates and soil types, and creates a mosaic of habitats for wildlife.
- Seed can be bought from commercial seed merchants or collected
- Efforts should be made to obtain seed from the immediate area to preserve the local provenance, or variation, within each species
- The seeds of many native plant species require special treatment to encourage germination.
- Preparation depends on the soil type and previous use of the land (see site preparation section)
- Deep ripping to at least 400 mm will be required
- Some direct seeding machines deep rip and scalp as part of the seeding process.
- Good weed control is essential and should begin 1 or 2 years before direct seeding
- The best management option is to control weeds before direct seeding. Use overspraying of selective herbicides as a recovery operation if the weed burden will affect establishment.
- The best time to sow in most of the medium to low rainfall areas is as soon as possible after the opening rains
- Sowing in the rain or just prior to rain helps increase success
- In higher rainfall areas (greater than 600mm) or sites prone to waterlogging, sowing in Sept/Oct has been successful.
- It is very important not to bury the seed too deep
- A bulking agent is needed to get a more even coverage of seeds.
- Red legged earth mite (RLEM), caterpillars and grasshoppers can be fatal to seedlings, especially when the emerging cotyledon first appears. Control them as early as possible.
- Sowing seed by hand or with a chest mounted or wheeled fertiliser spreader is useful for small areas or in inaccessible country
- Mechanical sowing can be done by a combine or large fertiliser spreader
- Specialised direct seeding equipment is available.