Bountiful broccoli

AS expected another summer hurtles by, promising little by means of sunshine and warm evenings. My bet would be for Iceland to win the 2018 World Cup rather than having a decent summer next year.

Having had a good old moan about the weather as we like to do in Britain, it’s not all that bad; weather extremes are limited and at least we know what to expect. A crop that continues to do well in our cool summers is broccoli.

Broccoli belongs in the Brassicaceae family with its full Latin name being Brassica oleracea. The word broccoli is an Italian word derived from the Latin brachium, meaning "arm" or "branch". There are two types of broccoli, one known as Sprouting broccoli and the other Calabrese.

Calabrese broccoli is what we consider broccoli to be; it’s the type we see in supermarkets all year round which consists of one large immature flower head, similar to a cauliflower, but green. The word Calabrese takes its name from Italian meaning "from Calabria". The large flower head is surrounded by smaller shoots that develop once the main head has been harvested. Calabrese crops from summer until the first onset of frost. Some good varieties include Broccoletto (sweet and quick maturing), Green Comet (early with lots of side shoots) and Romanesco tender and flavoursome with a lime-green head).

Calabrese in particular doesn’t like being transplanted, therefore sowing direct in spring will reduce the risk of bolting. Station sow 2-3 seeds, thinning to leave the strongest. Spacing is dependent on variety and desired growth. Close spacing will encourage a small terminal spear to develop suppressing side shoots, whereas wider spacing will mean higher yields. Spacing can range from 7.5cm apart with 60cm between rows to 15cm apart and 30cm between rows.

Sprouting broccoli produces a succession of small flower heads that can be cropped over a long season from early winter to late spring. It is tolerant of poor soils and cold areas. Purple varieties are hardier and more productive than white types. Dependant on the variety, sprouting broccoli can be harvested at different periods. Purple Sprouting Early has been developed to be ready from early winter whereas Purple Sprouting Late is ready in mid-spring with other varieties cropping in between.

Seeds can be sown either direct from mid to late spring or under glass in early spring in modules to transplant out. For early spring crops, seeds can be sown under glass from late summer to early autumn and transplanted out after being hardened off from late winter to mid spring. Sprouting broccoli has a very long growing season and needs plenty of space. Final spacing can vary from 45cm to 75cm apart.

Most crops in the Brassica family thrive in a sunny position, grown in firm moisture-retentive soil that is free draining. If temperatures get really hot in summer, Brassicas are prone to drying out and bolting, therefore cooler summer temperatures are preferred. Brassicas are heavy feeders, however, too much nitrogen would encourage too much undesired soft leafy growth. Earth up sprouting broccoli or stake to add stability before it becomes top-heavy.

Harvest sprouting broccoli when the head has formed before the flowers open. Regular harvesting will encourage further side shoots, but make sure you don’t remove all the stems as this will render the plant unproductive and woody. With Calabrese, harvest the central head while the buds are firm and tight. Side shoots should start to develop; harvest these as you would with sprouting broccoli.

Brassicas are affected by a range of pests and disease; one notable fungal disease is club root. The roots become swollen, causing severe stunting of growth and the leaves become yellow and wilt. Affected plant material should be removed and destroyed. Raising the pH of the soil slightly by liming will help prevent club root by creating unfavourable conditions for it to take hold. Rotating your crops annually will also help discourage the disease.

Other pests for Brassicas include birds in particular. Netting Brassicas with a fine mesh will help keep large pests away and prevent butterflies laying their eggs on the leaves.

Jobs for the week

Sow spring cabbage, turnips, Oriental vegetables, chicory, fennel, and autumn/winter salads.

Carrots can still be sown, but beware of carrot fly when thinning existing seedlings.

Plant out leeks and brassicas for a winter supply, if not yet done.

Complete summer pruning of gooseberries, redcurrants and white currants.

Check plants regularly for aphids.

Watch out for potato blight and tomato blight.

Look out for asparagus beetle.

Keep an early eye out for the sunken brown patches of blossom end rot on tomatoes.

Deal with woolly aphid, plum rust, pear leaf blister mite and pear rust.

DIARY DATES

July 23 to September 4: Rocket Science Summer Family Fun

Families can embark on an out-of-this-world adventure this summer in Harrogate as the northernmost RHS Garden goes intergalactic. Youngsters can take part in their very own space mission to Mars on a space-themed garden trail, enjoy stratospheric storytelling with the Garden Detectives, create cosmic crafts, and discover how our feathered friends have influenced flight and space exploration during spectacular birds-of-prey flying displays. Normal garden admission.

Summer Sundays

Bring a picnic and enjoy live music in the beautiful surroundings of Harlow Carr every Sunday throughout July and August from 1 to 4pm. Normal garden admission.