RHS Level 2 Certificate

Week 20 – Outdoor food production. Vegetables – Brassicas and salad vegetables

Learning outcomes

Brassicas and Salad Leaves and misc veg.:For named varieties of each of cabbage (spring, summer and winter) and Brussels Sprouts, and for named varieties of each of lettuce (crisphead, butterhead, Cos and cut and come again), outdoor cucumber and courgette, state state:

1.1 state the place in seasonal rotation and successional cropping

1.2 state cultivation, propagation and care requirements1.3 state 1 pests and 1 disease, their symptoms and their

control1.4 state harvesting period and technique and storage1.5 Describe how quality and yield for each may be

determined by the following: base and top dressings, thinning, weed control, crop support, irrigation and pest and disease control

Brassicas – Cabbage Varieties

Spring: ‘Durham Early’ or ‘Pixie’Summer: ‘Greyhound’ or ‘Derby Day’Winter: Smooth – ‘Tundra’

–Savoy – ‘Savoy King F1’

Brassicas – general points

Rotation – after legumes and before roots Soil resident pests and diseases are

common so rotation has real benefits Very heavy feeders – need lots of nitrogen.

Legumes provide some; manuring in Autumn and applying base dressing before sowing and then feeding during the season provides the balance.

Need well consolidated soil to avoid wind rock.

Brassicas – more general points

• Acid soil restricts growth and encourages club root disease – soil pH needs to be 7 or above so lime in spring if necessary.

• Sow either in deep modules in an unheated greenhouse or in a seed bed and transplant when four true leaves have formed.

• Final spacings - 30cm centres for spring cabbage, 40cm for winter and summer cabbage.

Brassicas – pests and diseases

Pigeons – net crop after sowing and again after planting out.

Cabbage root fly – very fine netting or cabbage collars

Club root – no cure; grow from seed, keep soil alkaline

Leaf spot (ring spot) - difenoconazole (but watch the harvest interval); good crop hygiene and spacing.

Salad leaves – Lettuce Varieties

Cos – upright, loose heads e.g. ‘Little Gem’

Crisphead – classic ‘iceberg’ lettuce e.g. ‘Avoncrisp’

Looseleaf – cut and come again, non-hearting e.g. ‘Green Salad Bowl’

Butter head – soft leaves, heart forming e.g. ‘All the Year Round’

Salad leaves etc – general points

Lettuce and cucumber are not in any rotation group. Many oriental salad leaves are brassicas- for example Pak Choi and Mizuna - and these should be rotated with the brassicas.

All salad vegetables require fertile soil and plenty of water. Watering needs to be consistently plentiful throughout the season if there is no regular rain fall.

Lettuce - sowing

Seed is subject to heat induced dormancy so sowing in summer should be in well watered drills, on overcast days, in the evening.

When mature, hearting lettuces bolt – so, sow a few seeds every two weeks to avoid a glut. Loose leaf lettuce are less prone to bolting, sow every three weeks.

Rich fertile soil with a pH over 7.

Salad leaves – pests and diseases

Slugs and snails Root aphid on

lettuce Botrytis on lettuce Mosaic virus

Outdoor cucumbers - varieties

Standard ridge cucumber – ‘Marketmore’

All-female ridge – ‘Paska F1’

Japanese – ‘Burpless Tasty Green’

Apple – ‘Crystal Apple

Outdoor cucumbers

Need very rich soil and plenty of water. Need warmth to germinate and to grow

successfully. Sow in May/June or if earlier then under glass with bottom heat. Plant in a sunny sheltered place.

Plant at at least 40cm centres and provide support for the vines to climb.

Feed with high potash liquid feed once the fruits start to set. Keep picking small fruit.

Cucumber pests and diseases

Slugs and snails Aphid Cucumber mosaic virus Powdery mildew

Courgettes

Essentially the same as outdoor cucumbers Pollination essential – do not remove male

flowers. Keep well watered – but water the soil, do

not splash the leaves. Keep picking – once seeds begin to mature

yield will fall. Varieties: ‘Tiger Cross’ F1 – CMV

resistance; ‘Gold Rush’ F1 – yellow fruit.

Learning outcomes

Brassicas and Salad Leaves and misc veg.:For named varieties of each of cabbage (spring, summer and winter) and Brussels Sprouts, and for named varieties of each of lettuce (crisphead, butterhead, Cos and cut and come again), outdoor cucumber and courgette, state state:

1.1 state the place in seasonal rotation and successional cropping

1.2 state cultivation, propagation and care requirements1.3 state 1 pests and 1 disease, their symptoms and their

control1.4 state harvesting period and technique and storage1.5 Describe how quality and yield for each may be

determined by the following: base and top dressings, thinning, weed control, crop support, irrigation and pest and disease control