• AGM plants

    AGM plants have been through a rigorous trial and assessment programme. They are:

    • Excellent for ordinary use in appropriate conditions
    • Available to buy
    • Of good constitution
    • Essentially stable in form & colour
    • Reasonably resistant to pests & diseases

The finest sweet peas – it’s all in the preparation

Behind every RHS plant trial lays an often-hidden world of planning and preparation. So how does a plant trial get transformed from the planning stage into a colourful summer display on the trials field?

Sweet Pea trial assessment at the National Sweet Pea Society event in summer at RHS Garden Wisley 2014Our current preparation work for the sweet pea trial at RHS Garden Wisley shows the range of tasks involved. We make sure that our horticultural trainees help with this preparation, as the work covers a wide range of horticultural skills.

Using the subsoiler back in autumnBack in the autumn we used a tractor-mounted subsoiler on the bed to break up any underlying compaction. 

Firming the soil on the Trials Field at RHS Garden WisleyThis was followed by a spader machine to break the soil down into manageable clods. Now, in the spring, we are rotavating, firming (using many pairs of RHS feet) and raking the bed level. Next we mark out the fence, path and planting areas, install the fence posts and apply fertiliser (based on soil analysis).

We then install drip-line irrigation and cover the planting areas with landscape fabric, which helps to prevent weeds and retain moisture. We mark the planting holes with small canes. Each group of plants is spaced 2m (6ft 6in) apart and the miniature varieties are planted in groups of 12 with 40cm (16in) between them. There is also space allocated for the containers and hanging baskets.

Sweet peas redy to transplantNow the fun begins, as we plant out all the sweet peas (which were sown in-house by our propagation team in the autumn).

We cut a cross in the landscape fabric, the sweet peas are planted and the fabric folded back. Following watering in, a chicken-wire fence is put up to stop them being eaten by rabbits.

The plants will grow rapidly through the spring, so the next task is to construct the cages for them to climb up. Do come and see them in all their glory this June!

Useful links

RHS advice on how to grow sweet peas

The National Sweet Pea Society

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