Seed sowing in containers in a protected environment Neil Barry

Seed propagation in a protected environment Protected environment - germination conditions can be optimised Allows seeds to be started when outside conditions would not allow growth – particularly important for half hardy and tender annuals

Types of protected environment Greenhouses Polytunnels Misting units Propagators Heated benches Cloches

Factors in this control (1) are: Temperature Growing medium, Water supply, Humidity Hygiene ……cont’d

Factors in this control (2) are: Light levels Light length P & D Feeding

Practical steps to control germination environment Use of sterile, moisture retentive, free draining seed compost Allows oxygen to enter the soil whilst holding water. Sterile compost reduces the risk of ‘damping off’ diseases. Supply of clean water – not rain water Reduces the risk of ‘damping off’ Use of heated propagator or heat pad To allow soil temperature to be controlled Light – use vermiculite or compost to cover seeds unless they need light to germinate. To provide the light conditions needed to germinate. Cultural hygiene A basic requirement of any propagation

Equipment Containers – seed trays, modular trays, root trainers. Seedlings often have shallow roots – so containers are shallow to avoid waste Propagator – may be a simple plastic cover for a seed tray or a more sophisticated heated unit. Conserves humidity and temperature. Heat pad/benches – thermostatically controlled and placed under the seed tray. Mist bench – usually commercial use, provides heating and misting.

Seed ‘compost’ 1 Fine textured growing media, free draining but moisture retentive. Little or no added nutrients – because these might scorch the roots as they emerge.

Seed ‘compost’ 2 Heat sterilised – to avoid introducing fungal diseases. Loam based or organic based – check pH if sowing pH sensitive species. Multi-purpose can contain too much nutrient and be coarse. OK for large seeds.

Seed Sowing – different types of seed Large seeds – sow individually into small pots or root trainers. Medium seeds – tap off your hand or station sow (sowing individual seeds at controlled spacings) in seed tray or sow into modules (two seeds per module if germination rates variable). Very small seed – mix 1:3 with very dry silver sand and tap off your hand or from a fold of paper.

Techniques for different sized seed Very small seed – mix 1:3 with very dry silver sand and tap off your hand or from a fold of paper. The sand shows you where you have sown. Use a seed tray. e.g Begonia semperflorens, Cultorum Group Clip on sowing Begonia seed (1 mins) http://www.youtube.com/watch?v=jSGExNoxAkw

Techniques for different sized seed Medium seeds – tap off your hand or station sow (sowing individual seeds at controlled spacings) in seed tray or sow into modules (two seeds per module if germination rates variable). e.g. Lactuca sativa

Techniques for different sized seed Large seeds – sow individually into small pots or root trainers. E.g. Cucurbita pepo Sowing above – 5 mins http://www.youtube.com/watch?v=vE13Snu0UEg

Sowing seeds into a seed tray

Sowing seeds into a seed tray For small or medium sized seed. Aim is to provide a well aerated, free draining but moisture retentive, even surfaced growing medium without large air pockets or lumps. Sow thinly to avoid overcrowding (competition) and disease.

Sowing seeds in a modular tray or root trainers (1)

Sowing seeds in a modular tray or root trainers (1) Used for those plants which resent root disturbance or for medium and larger seeds. No need to prick out so less labour intensive

Sowing seeds in a modular tray or root trainers (2) Takes up more space for fewer plants Unlike seed trays they tend not to be re-useable. Can sow two seeds per station and remove the weaker seedling to avoid gaps.

Pricking out Required for seeds that have been grown in a seed tray. Moves the seedlings from the seed tray into individual modules or pots to grow on. Requires a degree of care and skill. Must be done at the right stage of growth or the seedlings will become crowded and ‘leggy’ and there is the risk of fungal disease. Pricked out into growing media containing some nutrients to sustain growth.

Pests Aphids – chemical or biological controls (under glass) Whitefly - chemical or biological controls (under glass) Two Spotted Mite - chemical or biological controls (under glass), cultural controls especially heat and humidity (like things hot and dry).

Diseases Damping off – seedling collapse. Control by hygiene and copper fungicide. Do not sow too thickly or over water. Virus – control sap suckers, sow certified seed, destroy affected plants. Downy mildew – no chemical controls. Hygiene, control humidity, grow resistant cultivars where available

Seed propagation outdoors Used for hardy annuals, hardy perennials and many vegetables. Cultivation – the aim is to produce a fine tilth Use of the Stale Seed Bed technique to reduce competition from weeds Sow either broadcast or in drills – the latter makes it easier to see which are weed seedlings. Keep watered and weeded, thin out to final spacing, provide support and dead head ornamentals as the season progresses to prolong the display

Pests and diseases outdoors Birds – use mesh barriers on vegetables, cotton between canes on new ornamentals. Aphids – as for protected, but biological controls not used. Slugs and snails – cultural controls, biological controls, hygiene, pellets (avoid metaldehyde). Downy mildew –as for protected. Powdery mildew – requires dry conditions so water correctly. Myclobutanil (Systhane). Virus – as for protected

Oes cwestinau gyda chi? Neil Barry