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About our Heleniums
Growing Heleniums Choosing: Heleniums come in a range of colours from deep red to pale yellow including blends, stripes and bands of colour. Heights vary from 2ft (60cm) to more than 5ft (150cm). it is possible to have Heleniums in full bloom from late June past the end of October by judicious choice of variety and deadheading. Use our new Helenium selector to help you decide. 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 light shade or 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 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 leaded, stems which, although shorter, will flower in mid September. More on this next year when we find out the impact on growth and vigour in the next year!
Heleniums flower best if dug up and split into individual plantlets discarding the old central stalk every 2 years or so. Only divide in spring - autumn division usually leads to failure! If planting individual shoots in spring leave about 20-30 (8-12") between plants for a very full effect that summer. You can plant at wider intervals up to 60cm if you are prepared to pinch out shoots in May to get bushier plants. The small plantlets can be planted directly into the ground if division is left until late April. Otherwise, pot them up in 9cm pots using a mix of multipurpose compost (10 parts), composted bark (2 parts), potting grit (1 part) and grow on in cold greenhouse, cold frame or under a cloche. Remember to water when dry. We normally start dividing plants in early February. Remember to label immediately if you are growing more than one variety. Plant out when around 4 - 6 in (10 - 15cm) tall.
End of Season Maintenance: From late August onwards you will begin to see new plantlets forming around the base of the plants - don't be tempted to split them now! (N.B. some cultivars don't produce these plantlets until early Spring). Once flowering is over the parent plants will begin to look a bit scruffy - cut back the flowered stems to as near to the soil as possible. Compost healthy stems (shredding / chopping up the stems helps them rot down quickly). Do not compost any weak or diseased plants - burn instead. Pests, Disease and Troubles: Heleniums are largely trouble free. From our conversations with other gardeners the top 3 problems to deal with are: Slugs and Snails: We have very little problem with these, but it seems others do. The problem is exacerbated because a lot of people won't use slug pellets for fear (unproven) of injuring wildlife. We find the best control is to ensure you have a large population of frogs and ground beetles - make a small pond (ours is about 90cm across and tucked away in a shady place and used to grow Iris Ensata cultivars). Use chipped bark as a mulch to encourage beetles. If you have a big problem and won't use pellets then picking the pests off by hand is the best solution. Don't plant in Autumn - keep plants acquired at this time in pots over winter where you can keep an eye on them, but remember to keep then very well watered. Don't plant small plants in Spring. Pot up divisions and plant out in late Spring when they are at least 9in / 22cm tall. Once the plants are up and growing slugs and snails won't be a problem. Leaf loss and spotting: is normally a result of the plants drying out for an extended period of time. Add lots of compost when planting and keep well watered. A seep hose or leaky pipe attached to a water butt is a good idea if you can't improve soil water retention. Loses over Winter: Again this is not a problem we have on our light sandy soil. We suspect that the main causes are: 1) Dividing at the wrong time, 2) Failure to divide the plants every 2 or 3 years 3) Water logging 4) Excess populations of slugs in winter / early spring. We have been slightly puzzled by people coming to us at plant fairs and asking about winter losses. On closer questioning it appears that they have purchased the biennial Rudbeckia hirta cultivars believing them to be similar to Heleniums. Always ask the "nurseryman" what you are buying and buy from real growers not people who buy plants on Saturday and knock them out at a so-called plant fair on Sunday. The only other pest that troubles these plants rarely is Eel Worm. These are microscopic organisms that can infest plants and cause stunted, distorted and weak growth. If the plants you buy are healthy and growing well then you are unlikely to be bothered by this. If present in your plants its best to dig them up and burn them and plant Heleniums somewhere else in the garden Propagation: Heleniums are best propagated by division. Seed-raised strains (e.g. Helena, Autumnale Mix) are available but the resulting plants won't necessarily look like their parents and are often far to tall for the their stems to hold them up. Named varieties must be propagated by vegetative methods to ensure true plants. Division: Divide plants in spring only - autumn division can result in many losses as the plantlets are usually too small to survive the wet, cold and attentions of slugs and snails. Plantlets are easily pulled away from the parent with roots attached and either replanted straight away or potted into 9cm pots and grown on until 6in / 15cm tall or more before planting out. Cuttings: New plants can be raised by taking small tip cuttings in spring and rooting them with a little bottom heat. This method can be used to clean stock of eel worm but does take some skill and patience. Take a cutting, grow it on rapidly and take another tip cutting as soon as it is big enough, disposing of the first cutting Helenium Naming and Identification We endeavour to keep naming up to date but new information is always coming to hand - please let us know if you have any additional information. |
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