Trying to grow healthy, vibrant flowers without proper soil chemistry is definitely a case of putting the cart before the horse. Good soil is the cornerstone of successful gardening, and it is important to make sure that your soil will meet the needs of your plants before the first seed is planted.
While soil chemistry is important no matter what types of plants or flowers you grow, it is particularly critical when it comes to working with bulbs, perennials or other plants that remain in the ground for than one season. The reason is that the chemistry of the soil can change from year to year. Therefore, if a formerly well blooming patch of the garden is looking a bit haggard, the first place to look is at the condition of the soil. Erosion, overuse of pesticides and fertilizers and a number of other factors can impact the quality of the soil, so it is important to test the soil if you suspect a problem.
Of course the soil should be tested anytime a new flower bed is prepared as well. It would be a mistake to assume that the soil chemistry is the same everywhere on your property, since the makeup of different patches of soil can be markedly different, due to past use, chemicals or residue in the ground, etc.
It is a good idea to have a thorough soil analysis done prior to planting a bed of flowers. Most major cities have several laboratories that do soil testing, so be sure to contact such a lab to have the soil analyzed for pH level, and for levels of important plant nutrients. If you are unsure where to get the soil tested, be sure to ask the staff at your local nursery or garden center for a recommendation.
After the present condition of the soil is known, you will be in a much better position to know how to amend the soil and make the changes that are needed. Once you know the pH level, the level of organic material in the soil, the amount of clay, amount of sand, etc., you will be able to choose the right additives to provide your plants with what they need to thrive.
The pH level of the soil can be a particularly critical factor when deciding what types of plants will work best. Most varieties of annuals, perennials and bulbs will grow well in a wide range of soil pH, but some plants have specific needs, and prefer soils that are either very alkaline or very acidic. If your pH range is outside the norm, or if it needs to be amended, there are a number of ways to accomplish this goal. For instance, limestone can be used to make acidic soil more alkaline, while sulfur is often used to make very alkaline soil more acidic. A pH level that is out of balance can also be helped by adding humus. This rich soil can be created at home by using a compost bin, or it can be purchased ready made from a garden center or nursery.
After you know the baseline content of your flower bed, it will be easier to track chemistry changes from year to year, and to make amendments as needed. The more you know about the quality of your soil, the more confident you can be that the plants you buy will thrive in your home garden.