Seedbed

• Aim: fine, firm, and moist seedbed
• Control weeds – cultivation, pre-emergent spray
• Bury turf & past crop residues

 

Sowing

• Depth – 1 - 1.5cm
• Broadcast sowing rate higher than drilling
• Seed to soil contact important
• Consolidation – rolling very important !
• Plant population critical to yield

 

Fertility – Overview

• Brassicas remove high levels of nutrient
• Every crop is different – fertilise based on expected crop yield and base fertility level
• Often “poor” paddocks – lift base levels for new pasture
• Do a soil test !

 

Fertility – In Fertility

• Respond strongly to N – drives production
• P critical for establishment – relatively immobile so down- the-spout gives best response
• Boron – mainly bulb crops, avoid seed burn
• pH – preferably over 5.6

 

Dry land production

• Can extract water from greater depth than pasture
• Kale & rape > than bulb crops
• Aim to have soil at max moisture capacity at sowing
• Sow early when more rain/less evaporation, or fallow to sow later

 

Irrigation

• Don’t let soil exceed refill point
• Small & frequent better
• Leave capacity for rain
• Monitor – probe or running balance of: (ET, rain, irrigation)
• Start early – hard to catch up

 

Weeds

• Have significant effect on yield
• Weed free seed bed ideal for establishment
• Pre-emergent sprays – rainfall for activation
• Post emergent sprays – spray when weeds are small
• Healthy fast growing crop can out compete weeds

 

Pests

• Can cause major damage – especially at establishment
• Check every few days around establishment (springtails), then weekly
• Insecticides can be applied as a spray after emergence, or as a seed treatment

 

Grazing Management

• Takes approx 4-6 weeks for rumen bacteria to adjust
• Introduce crops slowly – build intake over 10 days
• Brassicas are easy to consume quickly, so don’t allow hungry animals access to large amounts - gorging
• Feed fiber before giving access to brassica
• Frosted crops can cause bloat & cold forage cause decrease in body temp & an increase in energy requirement
• Provide plenty of water – lack of water = lower intake
• Nitrate poisoning due to late N - allow time to adjust, reduce rate of intake
• Shift fences at least daily for less trampling/wastage, long thin faces

 

Crop Measuring

• If you don’t measure it – how can you manage it?
• Yield (kgDM/ha) = average fresh weight/m2 (kg) x (DM%100) x 10,000
• DM% = dry weight (g) / wet weight (g) x 100