Growing advice - Sweet Peas
Sweet peas were first introduced into Britain in the late 1600s
and have been giving gardeners great pleasure ever since. Sweet
peas are wonderfully versatile and give colour and fragrance wherever
they are planted. They make ideal cut flowers and low growing
varieties have been carefully developed that require little or
no staking making them suitable for bed, borders and edging. The
most commonly grown types of sweet peas are the Spencer and Grandiflora
cultivars. Both forms climb using twisting leaf tendrils around
supports (man-made or other plants and shrubs). The Spencer types
have large flowers and may grow as large as 2 - 3m (6 - 10ft)
tall. The Grandiflora forms have smaller flowers but are generally
more highly scented. Dwarf sweet peas grow to about 90cm (3ft)
and make superb tub, hanging basket or Flower Pouch subjects.
Some varieties have also been developed with no tendrils and this
encourages more flowers.
How to Sow for Best Results
The seed colour varies from a pale cream through to black. Some
authorities have said that the darker seeds may need a little
more help to germinate than the pale ones. If you have had problems
with germination try giving them a helping hand. This is often
called scarifying, soaking or chipping. The surface of the seed
has a hard coating that stops moisture being absorbed and this
can stop or reduce the germination of the seed. All that is needed
to help this is for the outer surface to be scratched, rubbed
or chipped away to allow the water to pass through. Use a small
piece of emery paper to rub over the seed coat; or very carefully,
using a sharp knife, chip away a small piece of the seed coat
at the opposite or furthest end of the seed to the "eye".
Soak the sweet pea seeds in a bowl of hand hot water for 2 hours
and then sow immediately.
Direct Sowing
Sweet peas can be sown in mid-autumn in pots (September/October)
or early spring in pots or most commonly directly into the soil
where they will flower (January to April). Plant during March
and April into drills about 2.5cm (1in) deep and about 7.5cm (3in)
apart. Mark the row swell and watch out for mice and birds which
may damage the seedlings or eat the seed before it has germinated.
Sowing in Pots
Sow two or three seeds 1cm (½in) deep in 7.5cm (3in) pots
(deep ones are the best), or root trainers (the smaller seedlings
should be removed when potting on). Some companies offer special
sweet pea tubes which are about 5cm (2in) in diameter and about
15cm (6in) deep. The compost should be moist, but definitely not
wet. Wet compost (which can even be the case straight from the
bag) will be cold and reduces the oxygen that the seeds need to
germinate. It may even stop the seeds germinating at all! If the
compost is too dry this will also cause problems. If this is the
case, sprinkle a small amount of warm, clean tap water over the
compost and leave it to soak in thoroughly. When the compost has
absorbed the water, take a small handful and squeeze it in your
fist: if water drips out it is too wet, so leave it for a short
while in a well ventilated spot to dry off. If it holds together
when you open your hand, it's just about right. You can now fill
your pot with the moist compost and you don't have to water it
again before you sow the seed.
Cover the pots or tubes with a sheet of glass or place in an
unheated propagator and keep the mat about 13-19C (55-65F) until
the seeds germinate. As soon as the seedlings start to appear
(approximately 10 - 20 days) move them to a well ventilated cold
frame. When the first or second pair of leaves has opened, pinch
out the growing tip to encourage stronger new growth to develop.
Pot the young plants on when they are about 5cm (2in) tall into
individual pots or plant outside when the soil starts to warm
up in the spring. Remove any small or weak seedlings.
If you are over-wintering seed sown in the autumn, try to keep
the frame as open as possible, to harden them off. If the weather
is very poor and frosts of below -2C (28F) are expected close
the frame and cover with matting, straw or old newspapers to insulate
it. Prop the frame lights open in heavy rain for ventilation.
Check the compost for dryness regularly. If this is the case,
add a little clean water from below, being careful not to over
water. Too much water can kill seedlings, as it can spread "damping
off fungi", and encourage other moulds and diseases.
Plant the young sweet peas in a sunny, open, well-drained but
humus rich soil. Transplant spring-sown seedlings in late spring
and autumn-sown seedlings in mid-spring. For the best results,
dig in lots of well-rotted manure in the autumn, then, three or
four weeks before you wish to plant, carefully rake into the soil
a well balanced, slow release granular fertiliser. Plant about
20cm (8in) apart and a few cms (½in) away from their support,
the bottom shoot should be just level with the soil.
Providing Supports
Sweet peas are often left to form bushes and using twigs, pea
sticks, netting or trellis to support them, they make very colourful
displays throughout the summer. "Wigwams'' and rows are the
most common arrangement. The plants can be gently tied into the
supports, but will soon use their tendrils to grab each other
and the support in order to climb. Water well, especially when
the plant is in full flower, use a liquid feed from mid-summer
at about fortnightly intervals. Dead-head the plants regularly
to encourage more flowers.
Training for Exhibition Quality Flowers
Exhibitors use a method called cordon training. This produces
fewer flowers but they are top-quality. Set up two 2m posts with
a taut wire stretched between top and bottom. Anchor the ends
of the wire tightly around the posts. Firmly attach a 2.2m (7ft)
cane to the wires and push well into the ground at 22cm (9in)
intervals. The rows should run north to south to give the plant
even sunlight. Leave the plant a couple of weeks after planting
to establish, then remove the weakest shoots, leaving the strongest
shoot. This one can then be trained up the cane. Tie the shoot
using raffia, tape or rings at each leaf joint or node. Remove
any side shoots, tendrils or any flower stems with less than four
buds. When the plants reach the top wire or the top of the cane,
untie each plant carefully and lay it along the ground to its
full length. When all the plants are untied, attach the shoot
tip to a new cane further up the row, so it reaches about 30cm
(1ft) up the new cane. Tie it in as before, and repeat for the
other plants. New flowers will be produced by the plant being
stimulated by the layering process.
Pests and Diseases
Keep an eve out for greenfly, whitefly, caterpillars and other
pests, if they become a problem, use a recommended proprietary
brand of insecticide. Mildew can, in some years, become a problem.
Try to avoid watering from above. Pick off any badly affected
leaves and spray with a recommended proprietary brand of fungicide.
Deadheading will promote more flowers and help reduce the spread
of any pests or disease.
General Care
Keep the plants regularly watered and feed with a general all-purpose
liquid fertiliser every 10 - 14 days. When the plants are in flower,
a regular feed with a high potash feed (most tomato feeds) will
also benefit them. Don't forget to deadhead and remove any damaged
flowers or leaves.
Garden Shopping Centre
|
