Oceanside Garden

Breaking Seed Dormancy

Getting seeds to germinate can be as simple as showing them some soil and moisture, waiting for a couple of days and seeing fresh green sprouts. But not all seeds are this easy. Many seeds in the Protea family, for example, have specific needs that have to be met to break their dormancy. This includes subjecting them to smoke. Others require scarification, or having the outer coating of the seed removed. Some want to be soaked in water. The list of special treatments is almost endless, with many seeds requiring more than one type of treatment.

You may be wondering why I am writing about seeds and germination right before winter sets in and not in spring. Well, many of the plants that interest me do sprout in the fall. This gives them the best chance to get established over mild winters, put on a lot of growth in spring and then prepare for the harshness of summer. Plants need to have built up a good strong root system if they are going to survive months without appreciable water during the summer drought.

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I have acquired a couple of seeds recently where there are no serious suggestions for germination. One offered – we don’t know how to break their dormancy, so we suggest you buy thousands of seed in the hope that one or two may do something, sometime. They also added that it may take a few years. Another seed had the suggestion that putting it in Emu dung may help. Fat chance of me finding much Emu dung laying around in Oregon!

In both of these cases, it is not that they would be problematic in the wild. Seeds have dormancy triggers for very specific reasons. They make sure that when they do germinate, they have the best possible chance of survival. Perhaps Emu dung is a good idea. Perhaps it indicates to the seed that it has a supply of food, and that there is something specific about Emu dung that sends a chemical trigger. There are some seeds that require a particular animal or bird to have eaten it. As it passes through their digestive system, the acid probably gets rid of the outer coating and it is delivered with a food source.

Many times, we don’t understand the triggers, or have to find ways to make the seed think it has been eaten. For many years, it was thought that the Proteas needed fire, only to learn that it was in fact chemicals from smoke that triggered them. People are still not certain what chemical it is, and different plants do want smoke from different things being burned.

Experimentation

When starting plants from seeds, these are some of the challenges that we face. We basically have to conduct small experiments to try and find out what works and what doesn’t. Whenever I try seeds that are new to me, I tend to divide them up into several batches. This assumes I have enough seed. Then I can do things slightly differently for each, such as putting some of them on bottom heat or not. I may subject some to wider temperature swings by leaving them outside.

There are some other tricks that you learn along the way. For example, if a seed has a shiny, tough coat, it will not absorb water and thus the chance of success is very low in the short term. It is possible that if left long enough, that coating will break down, but that could take years. So, scarification can help. I have also been using hydrogen peroxide treatments more recently. It can really soften up a hard coating. A 1% solution for 24 hours seems to do the trick.

Another trick, especially for seeds that I expect to be slow in germination, is the use of fungicides. I have been trying two different techniques. The first is to dust the seeds in a powdered fungicide. The second is to water the plants in a liquid fungicide. The former is better when first planting the seeds. The latter really helps stop the onset of liverworts when germination takes a long time or the seeds are under mist.

Better Documentation

Both techniques are helping. I would often see dark patches forming in my nursery pots where a seed had been. Those had basically been attacked by mold. There is a lot less of that now. Results of my germination experiments will be included on the plant pages going forward, but not all of my previous attempts were properly documented.

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General

Proteoid Roots

The Plant kingdom is amazingly diverse and still quite unknown in many ways. As I have become fascinated with plants from the Proteaceae family, I have found out just how recent our understanding is about these plants and some of the things that make them special. I wrote about one of these some time ago, and that concerned their requirement for smoke as a way to break seed dormancy. In the past people thought they needed fire, but in the 1990s researchers found that it is chemicals in the smoke that was the important element. Since then, propagation techniques for many plants that appear after fire has swept through an area, have been revolutionized. Plants that used to have germination rates of a few percent, now see 90+% germination rates.

But what I want to talk about in this blog are roots. Again, this is a fairly recent discovery, this one going back a little further to 1960, but still not fully understood to this day. A hundred years ago, it was noticed that some Protea had roots that were different from others. Nobody knew why. The reason why I am writing this blog is because I saw these roots for the first time when I was repotting a Banksia. The term Proteoid roots was established in 1960 by H.M. Purnell who described them as a root with “dense clusters of rootlets of limited growth.” After extensive examination they were found in a number of species and genera within the Proteaceae family and today it is known that every genus except one grows these roots when required.

Proteoid roots on a Banksia ashbyi ‘Dwarf’

Purnell suggested that these roots were associated with the uptake of nutrients from the impoverished soils found in South Africa and Australia where these plants naturally grow – similar to the soils I have on the Oregon Coast. Most plants form a symbiotic relationship with mycorrhizal fungi.

Mycorrhizal fungi extract the minerals necessary for plant growth from the soil and give them to the plants in a liquid form that can be absorbed by the plant roots. In return, the plants support the fungi, giving them sugars and starches. But mycorrhizal fungi appear to not exist in the soils that these plants evolved in. This could be for one of two reasons: either the mycorrhizal fungi did not or could not live there, or that the soils are so lean that the plants cannot afford to give up any of their product of photosynthesis. These plants basically never shed their leaves.

Gondwanan roots

Proteas evolved in the ancient supercontinent called Gondwana, but proteoid roots could be older than that because they have been shown to exist in plants from the Northern Hemisphere and thus arguably evolved when Pangea existed (about 250 million years ago). Other species have been shown to use this technique, especially those from the Mediterranean region. Some researchers disagree and say that the Proteoid root clusters from the Northern Hemisphere are different and may have been an independent development.

One paper suggests that proteoid roots in Lupins only developed 2.5 to 3 million years ago and that the only plants outside of the Proteaceae family that have these roots are nitrogen fixing plants. While that may be true for Northern Hemisphere plants, other Gondwanan plants do have similar root forms, although they appear to not be called Proteoid roots. The White Lupin (Lupinus albus) is an interesting Northern Hemisphere example because it is a food crop that exhibits this root formation, and so this plant is receiving a lot of attention from agricultural companies. This may finish up solving some of the many unknowns about these roots, but they may also be different from the true proteoid roots.

Without the mycorrhizal fungi, the plants have to extract nutrients themselves and that is the job of the proteoid roots. Normally the phosphorous is so tightly bound to other materials that it is not available to the plant. Proteoid roots exude acid, carboxylates, and other substances into the soil that break down minerals and allows phosphorous, iron, copper and other nutrients to be absorbed.

This is not a slow process – it is done in a burst over a period of just 2 or 3 days. It is believed that this is done to stop other microorganisms from being able to sniff them out and taking some for themselves. They have become so efficient at doing this that if you were to feed these plants with a balanced fertilizer, you would probably kill them. They would literally overdose on phosphorous. Some studies have found that Proteoid roots are up to 13 times more efficient at absorbing phosphorous that typical roots.

More Research Required

A lot remains unknown. The plant doesn’t always have these roots. They are grown at times and then reabsorbs them at others. It is expected that they are created when certain nutrients are deficient, but research so far has been inconclusive. It is also unclear why they then remove them rather than just keeping them until needed. If you want to learn more about this you might be interested in reading this research paper from 1999.

General

Garden Planning

The planning of the garden involves me and the garden in equal measure. It is not me deciding what I am going to do with the garden, I get ideas, let them mull around in my mind and eventually the idea either forms or it goes away. The garden speaks to me and either accepts or rejects the ideas. OK – I know that is not what is really going on, but it works for me. One example is related to the lower part of the garden on the far side of the Portal.

It happened when I was building the deer fencing from the Portal along the length of the property. I had already planted a Kennedia nigricans on the Portal, which is a black flowered Australia climber. I had also recently managed to acquire a Leucadendron ‘Ebony’ a black leaved coneflower – also from Australia. I hadn’t necessarily wanted this to be a southern hemisphere garden – that is slated for the bank on the other side of the Portal. Another plant that I had put under the Portal was Impatience tinctorial, a plant that is predominantly white flowered, with a deep red throat, shaped somewhat like an orchid.

We started talking about what other black or white flowered plants we already had, either from their leaves or blossoms, that could be put along the pathway and thus planning for the Tuxedo garden was underway. The pathway is about 20 feet long with a dog leg in it. I already knew what I want to do at the end of fencing, on the protected side away from the deer – that is where I want to put a fairy garden. It is under the shade of some large pine trees and does not get much sun at any time of the year.

So, then the question becomes, how do you transition from a tuxedo garden to a fairy garden. They have to be joined by Whimsy Way! Then it needs a small gate that goes through the fence into the fairy garden. Above the gate, which must have a big knocker, it will be inscribed – “Only children or those with the heart of a child may enter,” or something like that. I am thinking it should be no more than 3′ tall but I am concerned about how many years it will be before I could not get through it! Whimsy Way will be filled with a riot of color, kind of Alice in Wonderland crazy. So, there will be tea pots, pitchers and other gay pottery and silverware filled with plants. We shall see how wild we become, but we have already been poking around in antique stores looking for just the right kind of whimsy.

We had always talked about using the triangles that had been cut out of the stringers for our steps as being a great art project. We could paint them in the colors of the rainbow and make them into a pathway. One idea was to gradient them from pale to intense colors as you go along the path. That would be great for Whimsy Way’s pathway and can start off white at Tuxedo lane and end up in full color as you go through the doorway into the fairy garden.

So while Tuxedo Lane is straight, Whimsy Way will be more flowing in multiple colors and go around a bend to the hobbit gate that leads to the Fairy garden. Whimsy Way will also connect to “The Garden of the Giants” which is the flat area of the bottom end of the garden. We have already planted Romneya coulteri ‘Butterfly’ in there which has just bloomed. The only way to describe those blossoms is large fried eggs. Also planted there is Echium fastuosum ‘Pride of Madeira’, a plant with huge towering blue flowers. Other plants, such as giant Alliums have been ordered and I am sure we will find many others to fill that space. It may even contain a Protea or two. Of course, most of this is just in my mind right now.

This is what Tuxedo Lane looks like today. There is a lot of work to do, but that will keep me busy for a few months and take a few years to even start to look like it should.

General

Happy Accident

There are times when I would love to say that something was 100% intentional. Perhaps there was some sub-conscious thing going on, but the most probable explanation is I got lucky. The happy accident became quite clear today when three plants started to shine individually, but it was the combination that was quite remarkable – especially since it involved a combination of bract, leaf and flower – all in a somewhat acid yellow. The picture looking down on the scene does not do it justice.

Anchored in the middle is a flowering dogwood ‘Venus’. While the flowers on this finish up white, they initially take on a yellow color and then grow in size until they are in full ‘bloom’. They have really settled in this year and have more than doubled in size and even more in the number of ‘blossoms’ on them. I put bloom in quotes because it is not actually a flower, instead it uses a few leaves that it colors up to look like a huge flower, when the actual flower in small and insignificant in the middle – yup, this tree is a faker! The good news is that bracts last much longer than petals and so we can expect them to continue their display for at least a month.

To the left is Picea pungens ‘Gebelle’s Golden Spring.’ This is a form of Blue Spruce that puts out this amazing new growth color. Eventually it fades to a blue/green. When Jesse and I saw this in a nursery, we knew it had to be one of our Christmas trees. That was 2017. Just like the dogwood bracts, the leaf color on this lasts for about 6 weeks before fading. This is a dwarf and probably will not get much larger than it currently is – perhaps a few inches per year at most.

The third plant in this happy accident is Rhododendron yakushimanum ‘Gold Prinz’. While it did bloom last year, it put on a much better display this year. Many plants in the upper streambed garden have really settled in this year and this Rhody got to be big enough to participate in this triumvirate. In future years it will get to be even more impressive.

The fact that the color match on these three is so close and happens at the same time makes for an amazing sight that just cannot be properly reflected in the picture. This is an accident that I would love to take claim for, but thank you Mother Nature for your inspiration.