As a good perennial border may be down for eight years or so, much depends on the initial preparation. The normal forking over will suffice but during this work the greatest care should be taken to get rid of anyof perennial weeds. If the strip is very weedy it would be worth while to have potatoes on the land for a year, for this is an excellent cleaning crop and thus having waited a season you would know that final success was assured.
The shallow digging or forking should always be done early in the autumn to allow the soil to settle before planting begins. Into the top 50 or 75 mm (2 or 3 in) should be forked sedge peat at a bucketful to the square metre. This will help to open up clay soils and provide the right medium for holding moisture in sandy soils. The tip is to use it dry with the clays and to damp it thoroughly before forking it into sandy soils. In addition, at the same time an organic fertilizer should be incorporated for this will release the plant foods slowly as the herbaceousneed them and also will provide material to help increase the humus content of the soil. All gardeners agree that it is soil texture that matters so much and everything should be done to improve the humus content by adding organic matter. Surface dressing of lime may have to be given on acid soils. This is particularly im-portant in the case of clay soils whose mechanical condition is improved when its acidity is controlled by lime additions. But never, however, use lime where it is proposed to grow lime-hating plants.
Sometimes a herbaceous border has to be planted on a virgin soil. The new garden-owner finds that he has to start from scratch and this usually means digging in the grass. Never make the mistake of burning the turf. Either skim off the turf shallowly and stack it sprinkling fish manure in between the layers at 105 g/m2 (3 oz per sq yd). In a year the turf should have turned into valuable ‘manure’. It can then be spread over the border. The alternative is to rotovate the border mechanically or to fork over several times. The turf will then rot down and provide humus and food.
Do not worry too much if your soil is very stony. You cannot get rid of every stone you see and there is no need to. Stones improve aeration. They make the ground more porous and keep it cooler during hot periods. Of course when they are too numerous, as in a gravel soil, they do make for trouble and the best thing to do in such a garden is to dig in as much well-rotted organic matter as you can and to fork into the top 75 or 100 mm (3 or 4 in) plenty of fine organic matter like sedge peat, even if you have to use it at a large bucketful per square metre.