Delphiniums, family and fun

Thursday, November 22, 2007

Open Days

Our annual open week end is this coming December 1st and 2nd. We’re open from 9am until 4pm. This is the time of year when most of the delphiniums are in flower and there are always a steady flow of visitors with cameras. Visitors love to see pollination demonstrations but mostly they just ogle the delphiniums and wonder how they can repeat that in their own garden. Simple, buy our plants and seeds and follow the instructions!

I love these open days. They are like an annual validation of the work we do and I just love to see people enjoying the sight.

This year the large paddock of seedlings on trial will not be there as we’re using the land to build another plastic house, which may well be started by then December 1st. There will still be plenty to see however as we have a few hundred flowering plants outside to supply pollen for the seed crossing. The two existing plastic houses (600 square metres total) are loaded with delphiniums in flower too.

Come and enjoy the day with us. If you are unable to make it at the week end then give us a call anyway and we’ll try to arrange a suitable time for you to drop in. We had two travelling couples, a mother and daughter from Canada and a couple from Sweden, call in last week so if you are avaid gardeners touring New Zealand, give us a call, we’ll be happy to arrange a time for you to visit.

More questions answered:

Do we ship plants to the USA?

Many folk ask if we ship plants outside New Zealand. The answer, unfortunately, is no – we only ship seeds. If, however, you would like a plant similar to say, Sarita or Sunrise (for example), then ask and we will suggest the best possible seedline to give you a great chance of producing similar plants.

Dwindles? What are they?

I was recently asked if I get “Dwindles”. At first I thought this may be a personal question that I don’t care to answer but then realised it may be referring to plants that gradually lose vigour and don’t come back the next year. Yes, we do get the occasional dwindle. In seed grown plants there is always a chance of the odd weak one. It is useful to remember that the soil in your garden can vary enormously over very small distances. You may have perfectly healthy soil in one place only to find that a couple of metres away there is either a disease problem, fertiliser imbalance or some physical difference that can have a large impact. Don’t always assume that “dwindles” are the fault of the plant.

How often should I divide my delphiniums?

Unfortunately this is very akin to asking “How long is a piece of string”. It depends on the plant, the climate, the soil and most of all, the personal preference of the gardener. As a general rule I suggest that if your delphiniums are taller than you would like, have thinner stems than ideal, are too crowded for your taste or have a very large crown but send up weak shoots, it may be time to divide. The best time to do this is in the very early spring when the new growth is either just about to start or very shortly afterwards (shoots are only just breaking buds or no more than an inch or so tall). Use whatever method suits you and damages the crown and roots the least.

We very rarely divide ours and don't have a vigour loss problem. I know
many folk do divide the clumps after a couple of years though, with good

The image to the right is of our delphiniums growing in the garden of Anne Cooke of Dawson Creek BC, Canada

Cheers for now


Sunday, November 4, 2007

Any Questions?

Now that autumn (ok, fall) has come to the northern hemisphere, gardeners are turning to bedding down their gardens for winter and planning for the spring. We know this because there has been a flurry of questions and seed orders are picking up again too. As well as answering questions by email I’m posting the information on the blog so that it’s available to all. If you have tips to offer, remedies to share or stories to tell, please feel free to comment or email me directly and so help build this resource. Names may be changed, or items remain anonymous, to protect the innocent.

I’ll try to keep this going every week. So, this week:

Can I grow delphiniums in heavy, water-logged clay?

A couple of years ago Syd, in zone 5 to 6, had trouble growing his plants in soil that “may get water logged from heavy rains, or snowmelt in the winter. It then takes awhile to dry out. If I dig a 12 inch hole and it rains heavily, the hole fills with water and takes days to dry out”. It can be difficult in summer too.

We had a chat about this and I suggest planting the delphiniums in raised beds with
their roots and potting mix only half in the ground. “Then add composted manure
or other light mulch to cover the root ball well. You could do this to the extent

that the planted plant looks like it is on a hole in the mulch. The delph will love the moist
clay but many of the roots will also be growing in the mulch which will be well
drained and full of oxygen and minerals. Once the mulch rots away replace with new. I will lay a pound to a penny that this solves the problem”.

Syd wrote back this week to say that it had, to a large degree, worked. If you have ground prone to water-logging then a similar strategy may help. I discovered this myself when one, very wet winter I simply dug up the delphiniums (loud sucking noise) in a similarly waterlogged garden, left them lying on the ground and promptly forgot about them until the spring, by which time they had grown new roots in the soil beneath and were well on the way to flowering. It worked a treat. Don’t worry about them getting too dry in the winter – they will be dormant and completely unconcerned, growing new roots when they need them.

Take care with insecticides, especially “systemics” on young seedlings.

Clouding the issue with Syd’s delphiniums was the fact that he was battling with compost fly in the propagation house. Not only do the larvae chew on the roots of young seedlings, the flies also spread damping off diseases. Syd had attacked the flies, a little too enthusiastically, with a systemic, granular insecticide. He killed them alright but nearly killed the seedlings too. They were looking pale and disinterested but when planted out recovered quite well.

There are a few issues here. Plants that have fought off damping off, or generally had a difficult start to life, seldom grow away as vigorously as they should. That’s one of the reasons Syd’s original plants didn’t grow well in the garden. Although the batch drenched with insecticide (to stop the compost fly and damping off) almost died, they grew away again when planted out, still free of the damping off pathogens. However, compost fly can be dealt with less severely and more safely. If compost fly is a problem I'd spray or, preferably, drench the soil with Bacillus Thuringiensis (BT) at the time of sowing. These bacteria attack the larvae of the compost fly and don’t damage the seedlings.

Once the seedlings are well emerged choose a warm, airy day (if you have any then) and water them again with the BT.

Thuricide, containing BT may also be used to control other caterpillars and it won’t harm beneficial insects. One source of supply is here:

It should be available at most garden centres.

How do I avoid “Damping Off”

This is a regular. Firstly, take care of your hygiene and be mindful of things that may spread disease (like Syd’s compost fly, or excessive water). Avoid overwatering seedlings and don’t water or spray overhead in conditions that will result in the seedlings being damp for more than an hour or so. You can find plenty of information about the control of damping off on our web site, here:

One of the best strategies is to use seed raising mix that has a trichoderma fungus incorporated. Your garden centres should be able to help with this. It works better than anything else you will find. It isn’t a chemical though and because it is such a cheap and effective control you may not find it promoted well.

If you can’t find this at a garden centre then try your local organic gardening club. I’m trying to find a northern hemisphere source on the Internet, but with little success. Can anyone help?

In New Zealand “Dalton’s” seed raising mix contains trichoderma fungus - and is simply wonderful.

Other stuff

The new plastic house we are building is taking shape. The 45 metre x 20 metre floor is finished, trenches for services dug and the construction team due to arrive in a week or three. We’re hoping to produce a crop of seed from this house in late summer. Don’t worry, we will be pollinating in the old house in just a week or so.

That’s all for now.