Monthly Archives: February 2020

Yellow pea like flowers of Genista blossom

Growing Dyers Greenweed (Genista tinctoria)

By Ashley Walker
Copyright 17th February 2020

Dyers broom, Dyer’s whin and Woadwaxen

Dyers Greenweed is a member of the Fabaceae or legume family. It is a typical shrubby broom native to the UK, growing in open pasture and heathland. It is a source of an excellent light fast lemon yellow dye similar to Weld. As its name suggests it was used with indigo (from Woad) to dye textiles various shades of green.

Horticulture

Like some other native dye plants, Greenweed has declined with the rise of modern agriculture so you are less likely to be able to forage for it. It mostly grows in the West and South of England and appears to prefer slightly acidic loamy clay soils though it will grow in alkaline soils if treated well. It can grow to a height of 1 to 2m and forms a bush, usually growing from a single base stem. There are dwarf varieties and a dwarf subspecies Genista littoralis. It is extremely hardy (surviving temperatures as low as -35ºC) so it should be possible to grow it in the far North. It loses its leaves in the winter and this maybe the reason it’s able to stand the sub-zero temperatures. It does not like being waterlogged but struggles in dry soils too when it needs to be watered occasionally during hot summers.

Dyers Greenweed bush growing in the author’s back garden.

Propagation

The seedpods of Greenweed turn black in late summer and on hot days burst apart scattering the  small pea shaped brown seed.

to show the seeds and seed pods of the plant

Seeds and pods of Dyers Greenweed

These may germinate in the Autumn or stay in the soil and germinate in the following spring. When I first tried to grow the plant from seed I followed the instructions to plant in the Autumn. Although some of the seeds germinated I found that the seedlings died during the winter. so I changed my strategy to planting in Spring which works very well and allows the seedlings to grow large enough during the first year to get through winter without problem.

Start seeds off indoors in modules or seed trays from March to April and plant out in June in a sunny position.

to show what a young seedling looks like

This very young Dyers Greenweed has self seeded but is in danger of being eaten by slugs.

The plants will grow large, so give them plenty of space and plant about a metre apart. They can be grown as a hedge in which case plant closer (say 20 to 25cm). The seedlings are very prone to slug and snail attack, so sowing the seed outdoors is very risky without protection. Cuttings can also be taken. Cut the woody 1 to 2 year old stems in Spring or Summer and just stick them into the soil. Only about 10 to 50% will take so plant more than you need. They will need watering regularly during the summer as they take a month or two to root.

Pests and diseases

shows red ladybird eating aphid pests

Ladybird to the rescue

Aphid on young shoot of Dyers Greenweed

Apart from slug and snail attack when young, the next big problem is aphids, which attack the young shoots in early Summer just when you want to be picking them for dye. The damage can be extensive and I sometimes have to resort to spraying them off with a jet of water from the hosepipe. Ladybird and hoverfly larvae usually get the aphid under control by mid to late Summer and the plants will recover enough to flower. There appears to be quite a bit of natural variation amongst plants with some consistently being attacked and others being generally free of the bugs. So if you find you have a resistant plant don’t hesitate to take cuttings from it.

Deer and other large herbivores also like to eat Greenweed.

Maintenance

The young shoots are best for dyeing. As the plant gets older it produces fewer shoots so the bush needs to be pruned or cut back at least once a year to encourage this new growth. In earlier times when the plant was grown as a source of dye it was typically harvested in the second year when the whole plant was cut down. During the early Spring/Summer take the first harvest of young shoots then cut back in August to get a second growth and harvest. Growing this plant as a low hedge is ideal.

Dyers Greenweed will regrow quickley after being cut back and produce lots of new shoots.

As a member of the legume family, Greenweed is capable of fixing nitrogen in its root nodules. As a result the plant does not need much, if any fertilizer and can grow on quite poor soils. Don’t plant Greenweed in your most fertile bed, so choose instead any bit of scrappy ground that gets full sun. Greenweed will not grow in heavy shade. Against a South facing wall or fence would be ideal. To help keep weeds down after planting you can add some thick mulch around the stems. Water if the soil becomes very dry.

Cultivars

Greenweed is grown as a decorative garden plant for its bright display of yellow blossom in mid to late Summer. If you grow several plants from seed they will probably have slightly different flowering times but if you buy a commercial cultivar each plant will flower at the same time. Commercial cultivars may also be less able to cope with strong pruning and are usually a lot smaller than the wild plant. Three cultivars of note are:

  • Royal Gold – 0.5 to 1m
  • Humifusa – dwarf variety
  • Flore Pleno – dwarf variety

Dyeing

The leaves and young shoots are treated much like Weld except if the stems are woody strip the leaves first. Boiling water is poured on the cut shoots and left for an hour or so to extract the dye. Fermenting the young shoots can also have excellent results. A small amount of alkali (lime water or a drop of ammonia) will bring out the yellow. Dye your textiles in the resulting extract at around 70ºC. This dye is excellent for silk. If dyeing green with indigo a slightly better result will be obtained if you dye indigo first and then over-dye with  Greenweed. The young shoots can be dried for storage and later use.

Silk and Cotton dyed with Dyers Greenweed

Japanese Indigo seedlings growing after dormancy is broken

Japanese Indigo and seed dormancy

By Ashley Walker
Copyright 14th February 2020

Persicaria tinctoria seed dormancy

Don’t throw out your old Japanese Indigo seed just yet.

Strange the things you think about when you are trying to get to sleep. For a week or two now I have noticed some germination activity going on in an old seed tray I moved outdoors at the end of last year. A few days ago (8th Feb) I took a closer look and realised that the seedlings were Japanese Indigo, so I’ve been thinking about this ever since.

The weather here has been very mild since before Christmas, with only a few night time frosts. During the day it’s been warm enough for Japanese Indigo to germinate but how has this happened? Japanese Indigo seeds only stay fertile for about a year, unless you freeze them, right? Well, clearly not, as my seedlings testify. I moved the seed tray indoors and yet more germinations. What is going on?

Although the label on the tray is long missing, I believe that this is a tray of seeds planted during late summer (September) of 2019. I wanted to see how old seeds could and still germinate. I admit my documentation was poor, but when it comes to plants my memory is quite good (more than can be said for my ability to remember anyone’s birthday). Germinations at the time were very poor. Only a handful of plants germinated and eventually I decided there would be no more so moved the tray outside. Outside, the tray has been exposed to all weathers including some hard frosts. Moss and even a Common Rush (Juncus effuses) had grown during the late Autumn and winter. But in all this time the seeds (from 2018) were not dead, but dormant.

Newly germinated Japanese Indigo seedlings growing in moss covered seed tray.

Seed dormancy is a fascinating subject as plants use all sorts of strategies. Some seeds are dormant from the moment they become ripe and need a period of vernalisation or their tough seed coats need to be scarified i.e. damaged before germination. Some seeds will stay viable for decades and others only last a year. I had thought that Japanese Indigo fell into the latter category, as germination rates steadily decline from age 6 months onwards. At 12 months of age few if any seeds will germinate even when sown in good conditions with warmth, light and moisture.

Persicaria tinctoria seed

Japanese Indigo seed.

I asked myself a question. What happens to an annual plant whose seed only survives a year, when there is a serious drought lasting for months? The plant dies out of course. But thinking about it, that’s crazy – no plant would use such a strategy unless it had evolved in a world where there were never droughts or forest fires etc. Japanese Indigo seed with its hard shiny black protective coat actually looks like it’s designed to last a considerable time.

I have a distant background in plant biology and this is what I think is going on:-

Fresh seed readily germinates. But if the environment is harsh and the seed is prevented from germinating, dormancy-inducing chemicals slowly accumulate within the seed. If the seed is exposed to soil bacteria and moisture the protective seed coat slowly breaks down until dormancy is broken. Alternatively the seeds might need to be vernalised to break dormancy. My seed tray was exposed to low temperatures and frost which may have done the job too. As soon as the conditions are suitable the seed then germinates.

So how can the small grower take advantage of this new finding? At the current time I do not know. You can certainly try sowing old seed into trays and leaving them outside during the winter. But, until I know exactly what mechanism was involved (scarification of the seed coat or vernalisation) I cannot say with any confidence how you can break dormancy quickly. More experimentation is needed.

If anyone out there has any further information I’d love to hear it.

Seedlings of Japanese Indigo break dormancy

Madder red and indigo bluedyed handspun and knitted jumper

From fleece to jumper in 6 years

By Ashley Walker
Copyright 11th February 2020

Ever since starting to grow our own dye plants I have wanted to create something I could wear, something that had been created from scratch. In the past I have been quite content to use bought materials to create works of art and craft but as I got older this has appealed less and less. I used to be confused by people who wanted to go back to creating the raw materials of their crafts. I thought that the raw materials were just tools to aid creativity and it was easy to buy the best. I never concerned myself about where they came from or how they had been produced. In time something changed and the thought of creating the raw materials myself began to be more important. I do not really understand the reasons why.

Growing our own dye plants was at first a sort of curiosity but one that propelled us into the world of spinning fleece. After all if you are prepared to grow your own dyes then it no longer seems right to use them to dye commercially manufactured textiles. What would be the point of that? So fleeces were obtained and Susan set out on the road of learning how to clean and mordant them. Later came carding, spinning (drop spindle and wheel) and plying into yarn with diversions into weaving and peg loom weaving. But learning all the steps to achieve a finished dyed garment has turned out to be a steep hill to climb.

Once I had learned how to spin I decided to dye sufficient fleece to make a jumper and trusted to my ability to learn how to knit when I had enough yarn.

Red madder dyed fleece being carded into rollags and spun into yarn

Red madder dyed fleece being carded into rollags, spun and wound into balls ready for knitting

The first photo I have of the beginning was taken in 2014 and shows some of the madder dyed fleece and yarn. However by the time this was taken I had probably been at it for quite a while. The dyeing process was done very carefully so as not to felt the wool. Chopped root was heated to about 60ºC and the fleece added. The dye pans were then placed in a hay box and left overnight. The next day the fleece would be removed and the chopped root at the bottom of the pan was pounded to help release more alizarin (the chief red dye of madder). The pot was then reheated and fleece reintroduced. This might be repeated 3 or more times before a suitable red was obtained.

Slowly, slowly I built up a good stock of dyed fleece to spin. The shades of red varied so I tried to blend the darkest with the lightest to obtain as even a result as possible. Even so the yarn shows a variation in colour which results in the very pleasing stripes of the finished jumper.
Once I had enough I needed a knitting pattern and I quickly found out that knitting patterns are created for consistently even commercial yarn, not home-spun. But with help from our good friend Brian Bond and a few test squares of my own knitting I ended up with a ‘sort of’ pattern I thought I could work to. This was adapted from a cardigan design in one of Brian’s books that I liked the look of. But that’s where it all came to a bit of a grinding halt. I started on the indigo dyed blue rib of one side of the jumper but after several weeks of trial, with much undoing I had barely got into the red. The level of concentration needed to knit was so great that the slightest distraction caused dropped or added stitches or some other mistake. Even when I thought I was concentrating I would often find myself knitting the wrong stitch and all this before I had got to the point of having to reduce the number of stitches or do any of the fancy edging. It was too much.

shows blue rib and a bit of the red dyed yarn knitted on circular needles

This is as far as I was able to take it on my own.

The wool and the bit of rib stayed in its bag for months until Susan took pity on me and decided to have a go herself. Susan can knit but has no experience of knitting with irregular yarn. So what did get knitted took a long time and wasn’t remotely the right shape or size. Susan was canny enough to know that sewing the pieces together would have resulted in an unusual jumper to say the least. So back into its bag it went. Then along came Tracey Ballard who said nonchalantly “Oh yes I’ll finish that off for you if you like”. It meant that my dream of doing it all myself was truly out the window but by this time I was a pushover to accept any help.

No doubt after much remedial work (we suspect more than has been admitted to) Tracey turned up with the finished jumper a few months later. It was exactly as I imagined it. It is heavy and warm and it fitted perfectly. It is the first new jumper I have worn since one my mum knitted me many years ago. I failed to do it all myself but the feeling when wearing it… well it’s indescribable. The colour red is bold and bright. Red was my fathers’ favourite colour. He would buy me red shirts for Christmas which I would never wear. Now I have a totally unique red jumper, one that could never be bought in a shop and one that I will be proud to wear and show off for the rest of my life. No doubt my Dad would have approved.

Ashley wearing the newly delivered jumper

The smile says it all.

Thanks to Susan and Brian for encouragement and advice. Special thanks to Tracey for finishing it off. It is friends and the small things that make life worth living even if they do take 6 years to complete.

shows rear of red madder dyed jumper with red stripes - the result of uneven dyeing

The back of the jumper showing the stripes produced by variations in the dye.