Herbaceous plants

Any herbaceous perennials that still need to be lifted and divided must be tackled now, without delay.

Spring division

(as opposed to autumn or winter) is becoming a less appealing option because a dry spring (as we’ve had in the past two years) makes it more difficult for the replanted roots to recover and grow on steadily.

• In beds where pernicious weeds such as bindweed and ground elder are still a problem, the lifted garden plants need to be washed down with a hose to get rid of the soil, making it easier to spot and remove the weed roots; plants are then potted up, to be returned to the border later, when the soil has been cleared of weeds.

Sweet peas

This time of the year is my preferred time for sowing sweet peas, rather than in the traditional autumn season, as there’ll be fewer setbacks from cold weather or pest attacks.

• We use Fyba’s Biodegradable Short-Life Sweet Pea Tubes, packed into a deep tray, filled loosely with a seed compost and tapped, not pushed, down, then watered. Sow the seeds ½in deep. Don’t score, scratch or clip seed it doesn’t need it.

• On a heated bench at a constant 60˚F, they’ll germinate within 10 days. Take them away from the heat when the first leaves show, and pinch out the tips when two pairs of leaves have grown, to encourage strong basal shoots. Weather permitting, they’ll go out in April/May.

Parsnips

Sow parsnips now. Most of our vegetable seeds are bought from the Organic Gardening Catalogue (www.organiccatalog.com). We justify the expense by starting off many crops under glass in a controlled environment to reduce wastage.

• Use sweet-pea tubes to start off your parsnips; this method gives a much higher success rate than direct sowing outdoors, where germination can be slow and erratic.

• Sow three seeds per tube, and upon germination remove the two weakest, leaving the best to grow on. Timing now gets critical; keep checking for the tiny root appearing at the bottom of the tube (normally very soon after first full leaf).

• Experience has taught me to get them in the garden without delay, so the tap root continues growing straight down, to give you long parsnips.

Broad Beans

• Mid March is a good time to sow broad beans outdoors, if soil conditions allow.

• Our soil is heavy loam over clay, so we don’t bother with autumn-sown broad beans as, nine times of 10, it’s too wet. But you don’t lose too much time by sowing as early as you can in spring.

• We use the Garden Organics Heritage Seed variety Crimson Flowered Broad Bean (www.gardenorganic.org.uk/hsl). This valuable seed is germinated in controlled conditions, under glass, three in a Jiffy 8cm coir pot, and planted out as soon as they come through.

By Philip Maddison, head gardener at Harrington Hall, Lincolnshire (www.harringtonhallgardens.co.uk)