This page lets you see what a typical soil analysis report looks like, the soil sample was taken from my tunnel.  It is quite a comprehensive report and I don't pretend to understand the technical terms used.  All I need to know is what if any deficiencies there are and what to add to correct them.

Lab Ref No. RS114466
Plant type; DAHLIA
Client: Andrew Allan Jnr.

Acidity, Alkalinity,Test
pH level of this sample: 7.0 NEUTRAL Suggested pH: 6.5 SLIGHTLY ACIDIC

Treatment required to correct pH: A slight reduction of pH is required to brinq to optimum, where all the major nutrients are most available. To achieve this add FLOWERS of SULPHUR at the rate of 6 ozs. per sq. yd. Very slow acting, will take many months to have full effect. Works best if added to warm soil, so Spring is best. Hoe into soil to avoid wind loss.

Nitrate Test LOW 5 Milligrams per litre (ppm) [0]

Phosphate Test LOW 9 Milligrams per litre (ppm) [0]

Potassium Test MODERATE 430 Milligrams per litre (ppm) [4]

Magnesium Test HIGH 250 Milligrams per litre (ppm) [4]

Soil Conductivity: 400 Microseimens/cm.*

* Low salinity, no treatment required.

Figures displayed in brackets thus [ ] refer to A.D.A·S. index numbers

Remarks; A liquid feeding programme, to supplement the base dressing is reported to benefit Dahlias.  Liquid feed Dahlias after 4 weeks in open ground with a balanced feed (1-1-1), e.g. CHEMPAK No. 3. Change to a higher ratio potash feed from JULY, e.g. CHEMPAK No. 4. Take care not to overfeed as oversize blooms will result.

Although soil compostion is fairly good and organic matter levels are about average, continue with the annual addition of well rotted organic matter. Incorporate well into soil. This will improve structure. increase humus levels and improve nutrient retention which are prone to leaching, (especially nitrates), due to the high sand fraction of the sample.

Drainage; Good
Aeration; Good
Workability: Good
Structure; Fair
Colour; Medium
Water Retention; Fair
Textural Class; Light Soil
Textural Group; Sandy Loam

Deficiences in nutrient levels can be effectively rectified by using either organic or chemical fertilizers. Usually chemical fertilizers are fast acting and almost immediately available to plants, organic fertilizers on the other hand are generally slow to release their nutrients, although there are some exceptions.
Both chemical and organic fertilizer options are detailed below, this allows you to choose the option you wish to follow. Just choose a nitrogen fertilizer, a phosphatic fertilizer and a potassium, and mix in the recommended amounts.
Use this as a BASE DRESSING a few weeks before planting. An alternative approach is to use a ready mixed compound fertilizer, at least two alternatives will be found in the appropriate section below.

Due to the current controversy, and public concern regarding the link between BSE and the human form, CJD. This laboratory is not recommending organic fertilisers based on mammalian sources, e.g. blood, bonemeal and hoof & horn. Although there is no conclusive evidence of a link, this advice has been given as a precaution. However Vitax Q4 is based on organic components and this is a good organic based alternative. Always wear gloves and avoid breathing any dust when handling any fertiisers.

NITROGEN; NITRATE of SODA (16%) 2 ozs. per sq yd. OR NITRATE of AMMONIA (33%) 1 oz. per sq yd.

PHOSPHATE; SUPERPHOSPHATE (17.5%) 2.5 ozs. per sq yd.

POTASSIUM; SULPHATE of POTASH (48%) 0.5 oz. per sq yd.

MAGNESIUM; None required

1. VITAX Q.4 @ The rate of 4.5. ozs. per sq. yd. OR 2. CHEMPAK B.T.D. @ The rate of 4.5. ozs. per sq. yd.

All figures in brackets refer to the percentage of that nutrient present in the fertiliser.