Growing
Heleniums
All Heleniums
are toxic if eaten and can cause skin irritation in some people.
Planting: Always add lots of compost when
planting. Heleniums like plenty of moisture but not being waterlogged; compost
helps sandy soils retain water and opens up clay soils to help them drain.
Heleniums are best in a sunny spot but will grow well in
sites that get sun for a fair part of the day.
Keep new plants well watered. Water all plants in dry spells.
If the flower petals are quilled and rolled it is sure sign that the plants are
too dry.
The taller varieties
require staking - we find that a cats cradle of string is fine when growing in
large drifts. Single plants can be staked. We find that stakes cut from trees
like Hazel are preferable to canes or green supports as the brown colour blends
well with the stems of Heleniums. Plants don't usually achieve their full height in the first year
after splitting - heights quoted below are for mature plants in our Cheshire
garden.
As mentioned above, the growing tips can be pinched out in May to
get bushier plants. You can also take tip cuttings in April which has the same
effect.
Some people also practice the "Chelsea Chop".
About the time of the Chelsea Flower Show (late May) cut back some of the plants
by about 20cm (8") - usually those at the front of the group. The remaining
plants will flower at the normal time, whilst the chopped ones will grow up and
flower later. We don't do the chop as prolonged flowering can be achieved by deadheading.
Dead heading will promote further flowers. If you
have the time and patience, cut off each spent bloom, taking the stem down to
just above a new tiny flower bud. If you have large drifts of plants to cope
with, shearing off the top 10-15cm (3-4") is just as effective. Some plant
books suggest that only some varieties of Heleniums will rebloom if deadheaded, and go on to
recommend H."Moerheim Beauty" on this basis. We have found have
that all cutlivars in our collection respond to deadheading by reblooming.
We are also experimenting with cutting
back hard early flowering cultivars after the first two flushes of bloom finish
and the plants are looking a bit tired. So far this is looking promising:-
cultivars like "Sahin's Early Flowerer", "Wyndley" and
"Goldfuchs" are able to send up new, fresh, stems which,
although shorter, will flower in mid September. Plants have flowered well in the
following year with no loss of vigour.