2015 Growing Dahlias Workshops

Practical propagating workshop

Following the success of the workshop last February and demand for more, we are holding two workshops in 2015 on propagating dahlias from tubers.  This workshop will also cover other aspects of successful dahlia growing. 

Withypitts Dahlias Ltd

A practical Dahlia Propagation workshop

Tuesday January 27th and February 10th 2015

St Peter's Church Centre, Street Lane, Ardingly. 
West Sussex RH17 6UN

10:00 am	Registration, Coffee & biscuits
10:30 am	Introduction & overview
10:45 am	Course begins! Starting tubers into growth Taking cutting from the tuber Prepare cutting to plant Insert cutting
11:15 am – 12:45 pm	Take your own cuttings with tuition and guidance
01:00 pm	Course ends – BUFFET LUNCH

What's included

This fully interactive and practical workshop is designed to equip participants with the skills to raise dahlia plants from tubers and a chance to have a go at their own propagation. You'll take home the results of your work to grow on in your garden including the tubers you have used.Sufficient background information will be given enabling the plants raised to be grown on to produce high quality blooms for use either commercially or in the home.

Each participant will be provided with all the materials needed:

• tubers from which to take cuttings
• seed tray
• compost
• rooting compound
• plant labels

Who should attend

This workshop is for all who wish to raise their own cuttings including commercial cut flower growers and for gardeners who want to fill their borders with colour and flowers for their own cutting garden.

PRICE: £50.00 inclusive. Limited places available. email courses@withypitts-dahlias.co.uk to book your place.

Dahlia jobs in June

If you haven't planted out now is the time to do so, just check there are no late frosts forecast but I'd say that for this year they are now past.  Begin the outdoor hygiene programme by keeping the ground well hoed to prevent weeds and to keep the ground aerated.  Stake all dahlias if not done before planting. 

7-10 days after planting the first top dressing may be applied.  A good general purpose fertiliser, fish, blood and bone is used at Withypitts Dahlias.  Tomorite is also good, not just for tomatoes!

Dahlia jobs in May

Oops, I seemd to have missed tips for April:
DAHLIA JOBS IN APRIL
Keep on taking cuttings until you have made sure that you have sufficient for your needs, although, the back end of April is getting a bit late for the plants to mature fully when planted out. 

Prick out dahlia seedlings as soon as they are big enough to handle and put into trays or pots.  Pot up the rooted cuttings into 90mm pots using a loam based compost such as John Innes No1.  We advise customers not to use multi purpose composts as it tends to kill recently rooted, tender dahlia cuttings.   

By mid-April some of the early cuttings will now be getting well ahead in their 90 mm pots; it's time to pot them on into 125 mm pots so that their  growth is not set back.  Especially important if you have bought ex-pot plants from a commercial grower.

Keep the hygiene programme going!  Any plants found to be diseased should be destroyed (burnt) as quickly as possible to prevent spread.

Plant out divided tubers about the middle of April.

Dahlia jobs in May
All your plants should be in 5 inch / 125 mm pots by the middle of May.  Stop plants when 5 to 6 inches, 125 mm 150 mm, tall or after 4 -5 pairs of leaves depending on the number of main flowering stems you wish to have.  Plants, whether seedlings or cuttings, should now be in your cold house or frame hardening off; do protect from frost!, if real chill threatens a fleece covering will do a great job.

Take any late cuttings should you need to produce plants for tuber stocks.  These will grow on but not begin flowering until, probably, late-August but will consequently go on longer if there are no frosts in late October / early November. Keep your hygiene programme going.

In the south and south-west start planting out dahlia plants when the weather is suitable and there seems to be no risk of a late frost.  As things are at present with the weather I anticipate beginning the planting out around the 3rd weekend in May.

Dahlia tasks in March

If you haven't already done so now is the time to start taking cuttings in your heated greenhouse. 
When the shoots are sturdy with two or three leaf joints they are ready to use as cuttings. Use a sharp knife to cut away the shoots a little above their base, where they join the crown. Take care not to cut the crown itself, which would prevent further shoots forming. Trim neatly immediately below a leaf joint, dip in rooting compound such as Strike and plant in either seed trays or pots filled with a gritty seed compost (John Innes Seed) or an equal mixture of peat and sand or seed compost. They may look a little droopy for 7-10 days, this is quite normal! Three weeks on and roots will begin to form. Once the cutting is clearly rooted and showing signs of growth, prick out and pot up in 9 cm pots into a well draining potting compost such as John Innes No 1. We strongly recommend that all purpose or multi purpose composts are not used as they may contain materials that will kill the delicate rooted cutting.

 As you can see in the image some of the cuttings have two leaf nodes and some three.  I don't believe there is a "rule" for this, my own rule is to keep the stem length fairly short and not at all leggy.  Most of the cuttings I take are between 3 and 5 cm.  The exceptions to this are those cultivars that just do not behave and grow not only very quickly but with well spaced leaf nodes.
I have seen other people suggesting cutting most of the leaves away and trimming those that are left, I have no idea what this achieves as we have a success rate of well over 95% of our cuttings rooting when taken as shown above.  Also, I would caution against keeping the cuttings within a polythene bag as there is a real danger of damping off.

Seeds

Towards the end of March any seeds you have harvested should be sown.  Keep the convex side of the seed upwards.  If not the roots will shoot upwards and lose enegy resulting in poor germination.

For those that do not have a heated greenhouse tubers may be started of in trays.

Propagation Workshop

Wow!  What a  great time we had at the workshop, thank you all for getting there in such awful weather conditions and for your very kind comments.

"So lovely to meet you both this morning.  I enjoyed it immensely and now hope to grow some of your wonderful dahlias! "

"Thank you so much for the informative workshop this morning.  Both James and I enjoyed the opportunity to learn from you how to propagate dahlias successfully.  It is not often you get the opportunity to spend time with someone so passionate and knowledgeable about his subject.

It was a friendly atmosphere and Hazel was so welcoming - thank you for the lunch.  I am looking forward to seeing our cuttings grow into beautiful flowers."

"Just a brief note to thank you for the most instructive and also enjoyable course yesterday at Ardingly.  I had taken dahlia cuttings previously but never with much success.  Hopefully I now know a lot more and will be able to grow those that I started yesterday and also to take others from last year’s tubers."

"Just wanted to say thank you of a lovely time on Friday. It was a very pleasant morning and very interesting."

"Really enjoyed my morning in Sussex meeting Richard and Hazel @WithypitDahlias .  Take a look at their fab dahlias - they are gorgeous!"

"Just back from fantastic propagation workshop at @WithypitDahlias. Thank you Richard and Hazel!"

Relaxing before we get down to work.

Dahlia jobs in February

For those with a heated greenhouse who wish to propagate from their own stock February is the time to get started if you haven't already.   We maintain  a minimum temperature of 15C in our propagation tunnel.  Take from the winter store the tubers you will be using to to raise your 2014 stock.  I am asked many times how many cuttings will come off one tuber.  This is a very difficult question to answer as cultivars vary so much.   Something like Lavender Perfection, which has in my experience always been difficult to propagate, will generally yield 6-8 cuttings.  Another such as Taratahi Lilac may yield as many as 20 plus cuttings.

Trim off the fibrous roots and stems and place carefully in shallow trays on a layer of sifted compost.   Cover lightly, but not the stems or crown, and water sparingly until the shoots begin to appear and then water normally.  Too much water in the very early stage before growth begins can cause tuber rot which is, obviously, not good, and rotting tubers smell horrible!

For many. or even most, cultivars shoots will begin to emerge in 2-3 weeks.

In the March blog I will describe how to take the cuttings that have grown and strike them.

For those with no heated greenhouse: carry out routine inspections as for January.

Practical propagating workshop

Following a number of requests we are running a workshop on propagating dahlias from tubers.

Withypitts Dahlias Ltd

A practical Dahlia Propagation workshop

Friday February 14^th 2014

Turners Hill, West Sussex. RH10 4PB
Change of Venue !!
St Peter's Church Centre, Street Lane, Ardingly. 
West Sussex RH17 6UN

10:00 am	Registration, Coffee & biscuits
10:30 am	Introduction & overview
10:45 am	Course begins! Starting tubers into growth Taking cutting from the tuber Prepare cutting to plant Insert cutting
11:15 am – 12:45 pm	Take your own cuttings with tuition and guidance
01:00 pm	Course ends – PLOUGHMAN'S LUNCH

What's included

This fully interactive and practical workshop is designed to equip participants with the skills to raise dahlia plants from tubers and a chance to have a go at their own propagation. You'll take home the results of your work to grow on in your garden including the tubers you have used. Sufficient background information will be given enabling the plants raised to be grown on to produce high quality blooms for use either commercially or in the home.

Each participant will be provided with all the materials needed:

• tubers from which to take cuttings
• seed tray
• compost
• rooting compound
• plant labels

Who should attend

This workshop is for all who wish to raise their own cuttings including commercial cut flower growers and for gardeners who want to fill their borders with colour and flowers for their own cutting garden.

PRICE: £30.00 inclusive. Limited places available.

Email: courses@withypitts-dahlias.co.uk to book your place. Invoices will be issued in due course.