To Herbar or KnotOrganoman
The trouble with a potager in the kitchen garden is that you cannot eat the vegetables without ruining the decorative display. So it is with the herb garden, too much picking and cutting and the aesthetics are gone. It makes sense therefore, to consign all the culinary herbs that you will use in the kitchen to the vegetable patch. If the latter is a potager, you must needs take on an allotment.
Having got that little problem out of the way, you can concentrate on your decorative herbary. As with vegetables, some herbs lend themselves to the strictures of the parterre, but others clearly do not, being variously informal upright, informal floppy, broomstyle, and clumpy. So a bit of each style, the formal and informal, should fit the bill.
As to growing conditions, there are, of course, exceptions, but of the range of herbs that you might wish to grow in your aesthetic herb garden, most enjoy hot, dry, and rather poor soils. Good drainage and sunny aspect are therefore key: poor is relative, and so in the very poor patch I chose for our herb garden, I worked in some balanced organic fertilizer.
Now you might wish to fashion your formal bit with knots, and there are one or two suitable herbs you can use for this. Rock hyssop (shorter than the common one), wall germander, cotton lavender, and possibly some of the upright thymes come to mind. But my experience with all of these is that as dwarf hedging they are not long-lived. If you want something that is going to be permanent, go for dwarf box (Buxus suffruticosa) and keep your fingers tightly crossed that it does not get attacked by the dreaded fungus. Knots, of course, require trimming, and if you interplant the patterns with other herbs, the logistics might prove insurmountable.
An easier option is to grow knotless patterns for your formal herbar, using low growing herblets such as the rock hyssop I have already mentioned. But there are many others, including compact marjoram, just a few inches high, a huge range of thymes, dwarf hypericums, dwarf lavenders, mat forming pinks, winter savory, and wall germander again.
Moving on to the informal bit, which will probably flank or surround the formal area, the range of plants is enormous. But first lets deal with some thugs. Be very wary of these worts - figwort, mugwort, ragwort, sneezewort, and soapwort. They are either too big, invasive, poisonous, or perhaps all three. Other troublemakers include squinancy (Phuopsis stylosa), attractive, but runs all over the place, buckler-leaved sorrel, an unattractive runabout, agrimony, very deep-rooted, sweet cicely, an attractive umbellifer with black seed heads, but very deep-rooted and a rampant self-seeder. If you are tempted to plant the more aromatic mints in your herbary dont. Always grow mints in a container, and dont sink that in the ground! Tansy and old-fashioned golden rod are rampant spreaders and should be studiously avoided unless you have oceans of space.
Having cast out all the evil-doers, lets look at some goodies. For structure, rosemary is good, but can get rather large. There is a good range of cultivars these days, and if you are pushed for space try growing 'Marenca' in an extra tall long tom. It is a ground hugging variety, and I am trying to get mine to grow vertically down the sides of the pot. Myrtle makes a nice rounded shrub, but needs shelter. For compactness, grow Myrtus communis ssp. tarentina (3ft). Lophomyrtus x ralphii can come in a purple-leaved form, but is bigger (6ft) and requires shelter and sun to colour well. The alpine mint bush, Prostanthera cuneata is a rounded shrub, has dark green foliage and clear white flowers, while Caryopteris x clandonensis 'Worcester Gold' is more open, with golden foliage and blue flowers. All these will provide the structural bones of your herb garden, among which to plant more sensuous herbaceous herbs.
Many of the catmints get far too big for most gardens, but the old-fashioned Nepeta x faassenii is much better behaved, spreading to about 18" or so, rather less in height. I also have Nepeta citriodora, almost prostrate with similar spread and delicious lemon-scented foliage. Common marjoram is highly aromatic and attractive to insects, but spreads and seeds all over the place. Named cultivars are better behaved and my favourite is Origanum 'Herrenhausen', leaves purple flushed and flower buds deep purple, opening deep pink, about 18" high. 'Hopleys' variety is similar but not quite so dark. 0. 'Buckland' grows to only about 8" high, has grey-green foliage and pink flowers. Common sage is a handsome plant if rather wide-spreading. The coloured and variegated-leaved sorts are neater. Neater still is the Spanish sage, Salvia lavandulifolia, smaller, quite silvery leaves, and 24" spread.
I love the blue-flowered annual borage, but watch it. It grows rapidly to 3ft or more and smothers everything. I deal with that by removing major side branches as they flop, progressively through the season. Grow the variegated Peucedanum ostruthium 'Daphnis' among it - white umbels to about 2½ ft. followed by nice seed heads, absolutely glorious. Anise hyssop is a good bee plant, and Agastache 'Firebird' is a dramatic cultivar with coppery flowers but somewhat tender. A. 'Red Fortune' has over-wintered well for me and I believe there is a blue form as well. Top the whole thing off with one or two tenderlings in pots. I cannot resist lemon verbena (Lippia citriodora), with highly lemon-scented leaves and salvia-like spires of small white flowers. It will grow to 5ft if you let it, but will take hard pruning as it comes into growth in the spring. For a sophisticated aroma try Tagetes lemmonii, no idea how to describe it, but unlike any other tagetes you might have come across. Scented leaf pelargoniums is another way, and there is a whole range of these.
As you can begin to see, there is a huge range of plants that you can label as herbs. The possibilities are endless, but whatever plants you choose, what you end up with is not just decorative, but a highly scented or even sensory garden, and a huge haven for bees and a host of other insects.
First published in the Rutland Group Newsletter, Winter 2007/2008
and subsequently in Cornucopia Issue 24
© Copyright for this article: Organoman
This article was taken from a copy of Cornucopia that was published in 2009. You could be reading these articles as they are published to a national audience, by subscribing to Cornucopia.