Podcast #8 – Water Works

We’ve finally gotten our summer here in the Pacific NW and it’s been pretty hot for a few weeks. The plants weren’t really prepared for this, so we’ve had to irrigate quite a bit to keep all that lush foliage happy. So the topic of this podcast is Water Works – focusing on how water moves in the soil and through plants.

One of the more interesting tidbits I found this week is a recent USDA study on growing more potatoes with less water. Sound impossible? Listen to find out the one single, simple thing that increased water use efficiency by 12% and reduced fertilizer runoff as well.

I also debunk the common myth about using drainage material in container plants. Research from 100 years ago demonstrated that water won’t cross textural barriers – so putting gravel in the bottom of the pot will actually create a bathtub effect rather than helping drainage.

The interview this week is with my garden – primarily the sunny south-facing side. I thought I’d take you on a tour to see what’s happened in the last 11 years. The photos below will help you visualize the interview.

The front yard in 2003. We’ve started taking out the turf and moving around trees and shrubs.

The front yard in 2003 from another angle. We’ve removed the second driveway and covered the area in wood chips. By the garage you can see two of the roses I dug up from the shady back yard and moved to the sunny front.

The new front yard, with fencing, more plants, a pond, and no turf.

The rhody-hydrangea corner in front of the arbor vitae hedge

The new street garden, with a new retaining wall to hold back the soil that used to wash into the street.  Everything not covered in plants is covered with wood chips.

This is the last podcast of the first “season” of The Informed Gardener. We’re going to take off for about a month before starting the next series. If you’ve got ideas about future topics, you can email me or post a comment here. In the meantime, you can listen to archived podcasts found on this blog; just click on “podcasts” on the right-hand menu.

Pop quiz time!

It’s the start of new semester.  Best way to get student’s attention is with a pop quiz right off the bat!  So in that vein, we’ll cross things up and give a quiz on Monday instead Friday.  Relax; to make things a little easier we’ll make this one a matching exercise.


Here goes.  At our recent Christmas tree conference in Austria, a colleague of mine at Oregon State University, Chal Landgren, presented the results of a study to look at the effectiveness of foliar fertilization on Nordmann fir.  Trees were grown in 15 gallon containers and assigned to one of four groups:

1)      control: no fertilizer

2)      soil applied controlled release fertilizer

3)      foliar nitrogen fertilizer

4)      soil applied fertilizer + foliar feed


Since Chal has yet to publish this I need to be a little careful with details but all fertilizers were commercially available products labeled and marketed for this purpose and were applied at manufacturers’ suggested rates and intervals.


At the end of the growing season, the trees were sampled for needle nitrogen content.  As a point of reference a needle nitrogen content of 1.5 – 1.6 % is usually deemed adequate for this species.


For your quiz: match the treatments listed above to the nitrogen concentrations below:

a)      1.14%

b)      1.91%

c)      0.98%

d)     1.70%


Answer and discussion tomorrow…



This past summer I had the chance to talk with an old friend of mine, Hamado Tapsoba, who I hadn’t seen in 15 years.  We had gone to graduate school together, but after graduation he headed back to Burkina Faso, and I headed up to Minnesota.  Anyway, while we were talking I told him that we were growing peanuts at the University (yes, I tell everybody — peanut news needs to be shared!).  When I told him some of the problems that we had with shorter seasons he asked why we weren’t growing Bambara groundnuts.  The answer was that I didn’t know what the heck Bambara groundnuts were.  Well, it turns out that these nuts are native to Western Africa and grow under the surface of the soil just like peanuts.  The reason Hamado recommended them to me was that they can have a growing cycle shorter than peanuts.  They can also be cooked like peanuts and have a flavor somewhat similar to chickpeas (or so I’m told).  I’ve had an incredible amount of difficulty finding Bambara in the US though I know that at one time they were grown here.  We have found a researcher in Burkina Faso who is willing to work with us, but that will probably take some time to get going.  Does anyone out there know about Bambara?  Especially where to buy plants or seed?)  It sounds like an exciting plant to work with.

Podcast #7 – Better Red Than Dead

This week’s podcast is dedicated to anthocyanins – those pigments that give plants red, blue, and purple colors. Anthocyanins are also powerful antioxidants, important visual signals for pollinators, and often deadly to insect pests. The myth of the week explains why red leaves aren’t usually a sign of phosphorus deficiency, but instead an indicator that anthocyanins can help plants survive many environmental stresses.

My interview this week is with Cass Turnbull, founder of PlantAmnesty, a Seattle organization dedicated to “ending the senseless torture and mutilation of trees and shrubs.”  My son Jack took the interview photos, and Cass supplied the others from the PlantAmnesty photo archive.  You’ll love the way she combines her educational message with humor!

Cass on her “throne”

One of the nonbotanical garden residents

A selection of PlantAmnesty humor

Please let me know what you think of the podcast; you can email me directly or post a comment on the blog. Suggestions for future podcasts are most welcome!

You guessed it…

The glorious Allium ‘Globemaster.’

Michelle and Laura B. nailed it, and Jennie had the correct genus.

A little taxonomic correction – it is NOT A. giganteum, as many catalogs and articles suggest, but rather a hybrid between A. macleanii and A. christophii; described by the breeder himself – Jan Bijl – in a 1990 issue of The Plantsman (vol. 12 pp 152-156).  Unless I’ve totally messed up and this is ‘Gladiator,’ not ‘Globemaster.’ They’re quite similar.

Big blobs of floriffic fun, none the less. A bit pricey at $5 to $8 per bulb, though. I only have five in the ol’ home garden – that’s about as "en masse" as I can afford.

Odds and Ends and Scrapple

School starts next week and so time is short, but I have a few quick thoughts to share with you before I get back to setting up class for next semester:

1.  A class called Plant Production appears to be more attractive to students than a class called Nursery Management and Production — even though the concepts taught are essentially the same.

2.  One of the greatest movies of all time, Caddyshack, includes a scene with milorganite.  I won’t tell you which scene so that you can discover for yourself!

3.  Yes, that is what I did during my vacation — watched Caddyshack.

4.  The paint company Sherwin Williams used to sell insecticides in the early 1900s and late 1800s — things like lead arsinate and Paris green — and they used the same logo to advertise these insecticides that they use for their paints today — go ahead, look it up — and then tell me, if you were a PR person for a pesticide firm would you use that logo?

5.  The peanuts are so close to being ripe I can almost taste them!

6.  There’s nothing quite as good as eating Dunkin Donuts and scrapple for breakfast (I spent the past week in Southeast PA — my hometown — and one of the few places that you can find scrapple).