Two years ago I wrote a post about ground covers I was trying to establish around the perennial vegetables to avoid having to weed and to keep in moisture. How have things on the ground worked out since then?
The creeping Jenny (Lysimachia nummularia) looked neat around the sea kale in the spring...
|Creeping Jenny growing around sea kale in the spring|
and is still doing a great job.
|Creeping Jenny growing around sea kale in late summer|
The kale is healthy despite the vigorous growth of the ground-cover. I do some occasional weeding of couch grass and dandelions. The couch grass has never been completely ousted from this plot and it emerges through the creeping Jenny. I don't think it would invade from a distance though, unlike the dandelion seeds which sneak in everywhere! The creeping Jenny spreads into the paths given the chance but is easy to pull out with the hands. I will also pull its stems back a bit from the crown of the kale plants over winter. They might be protective from winter wet but I'm concerned about the opposite effect - that stems that die and decompose may cause rotting at the neck of the kale.
I have changed things around in the garden quite a bit over the last couple of years in order to find combinations of plants that will be self-sustaining. I can't quite remember why, but the wild strawberries are now around the elephant garlic and globe artichokes and cardoon. Earlier in the year they had formed a dense mat and were fruiting prolifically but now the couch grass has invaded quite badly. I may need to pull back the strawberries and dig it out as it will compete strongly with the vegetables.
|Wild strawberries growing around elephant garlic|
In another change I've recently pulled the Siberian purslane out from beneath the brassicas. It spread quickly and formed a dense cover (it is the flowering mass beneath the tall kale on the left in the photo below).
|Siberian purslane growing under perennial brassicas|
But it has grown increasingly messy as the season has gone on, and besides, I don't especially rate its flavour. I've resown the area with clover. Clover is a nitrogen fixing legume (the Rhizobium bacteria which live in nodules on its roots acquire nitrogen from the atmosphere which is then made available to the clover). As I understand it, if I cut the clover at intervals it will shed root tissue as it seeks to re-establish a balanced root to leaf ratio. Then this plant material will breakdown in the soil and become available to the nitrogen-hungry brassicas. But whether the clover can cope with the shade beneath the brassicas will need to be monitored.
I carried out my plan to plant silverweed around the skirret and, as I hoped, it did prove effective to harvest tubers from both plants at the same time. (Silverweed produces crisp, tasty but tiny tubers. I'm interested in growing and regularly harvesting various silverweed plants in the hope of finding a plant which produces bigger tubers).
|Silverweed growing around skirret|
There is more thinking to be done on this one though because the silverweed has struggled to re-establish a thick cover on the bed in the following season making some weeding necessary. Allowing a fast-growing annual ground-cover such as winter purslane (whose flavour I prefer to Siberian purslane) to reseed itself in the plot alongside the silverweed might work. (You might note in the photo above that most of my skirret plants didn't make it through last winter. I'm not sure why. New plants from seed have been planted to the right, currently mulched with grass clippings).
Here is the chamomile covering the Babington leek bed.
|Chamomile growing on the Babington leek bed|
There is no sign of the leeks - the leek flower stems with their top-setting bulbils have been harvested and the leek bulbs will lie beneath the soil until they emerge in late winter/early spring. I've started to intermingle non-flowering garden sorrel plants with the chamomile to increase the harvest from the bed. In March last year I wrote, "The chamomile was chosen for its anti-fungal properties in the hope that it might guard against leek rust. But it is the Treneague form, very ground-hugging, and I'm wondering now whether a slightly taller plant, perhaps the species Chamaemelum nobile, might be better for promoting longer white stems on the leeks." Reviewing this now I can say that the leeks didn't get rust last year but they did this year so the 'guarding against leek rust' idea didn't work. And the chamomile (sold to me as Treneague) flowered and so revealed itself to be the species Chamaemelum nobile (Roman chamomile) after all! As its height is now quite a bit more than the four inches often quoted I'll be interested to see if it helps to promote longer white stems on the leeks next year.
Of the other ground covers I mentioned in August 2013 (lamb's lettuce, bugle and creeping thyme) I am now less keen on lamb's lettuce as a ground cover which I planted around the asparagus but which formed a huge mass of fibrous moisture sapping root by the end of the season (came in like a lamb and went out like a lion really!) I planted bugle in the deep shade beneath the Daubenton kale but I'm not sure if it is still there (I forgot to look on my last visit). The creeping thyme has done its job though.
Here it is around some tree onions and chicory.
|Creeping thyme with chicory and tree onions|
It hasn't spread over the whole bed yet so I allowed wild forget-me-nots to fill the gaps (the now grey foliage masses in the fore- and background) but I like the idea of planting white and purple forms of the thyme alongside this pink one.
And that just about covers it!
N.B. I sell a range of perennial vegetable plants on my website.