Fertilizing Your Bulbs

Bulbs flower year after year in your garden and provide you with a spectacular display of color. Bulbs are fairly easy to plant and care for, but they still require a bit of effort in the initial stages in order to give you that well deserved visual reward come spring. The key to successful bulb planting is the fertilizer.

Compost and chemical fertilizers are common material used in gardening. While it is true that bulbs can survive without fertilizer, they will thrive even more and flower more rigorously if given a little bit of extra attention through proper fertilization.

How often?

Bulbs should be fertilized twice a year for you to obtain the best results. This should be done once in the beginning of spring, before the bulb flowers. This fertilization acts to help your bulb store nutrients over the winter months. The second fertilization should be done in autumn, right after first frost which helps the bulb produce better flower come spring.

What type?

Chemical fertilizers

You can use bulb fertilizer which can be purchased in your home gardening store, of you can make your own by buying the nutrients that your bulbs need. These nutrients include nitrogen, potassium, and phosphorus.

Nitrogen (N) is important for plant foliage, providing the bulb with nutrients to put out healthy foliage that will absorb more much needed energy from the sun. Potassium (K) helps the bulb fend off diseases and phosphorus (P) helps the bulb multiply and produce bigger and more vibrant-colored flowers. Because the main purpose of planting flowering bulbs are their flowers, purchase fertilizers with high phosphorus ratios (the middle number in the N-P-K ratio like 4-10-5).

Nutrient formulation (N-P-K) such as 9-9-6, 4-10-6, 5-10-20 or 10-10-20 are available in the market. Which formulation you use depends on the type of bulbs you are planting. The common formulation 9-9-6 is ideal for most types of bulbs. These include garden lilies and tulips. Daffodils love 5-10-20 or 10-10-20. Garden lilies (Lilium species) should be fertilized with a 5-10-10 or 10-20-20 garden formulation in the spring just as the shoots are emerging. You should follow the recommended application rates that should be written on the package.

Compost and Bone Meal

You can also consider using compost and making your own. Guides on how to make your own compost is available in previous chapters and you can also find tips on this through online resources and home gardening books and magazines. Consider adding some bone meal to your compost which will give the bulb the extra boost of phosphorus so desired.

Blood Meal

Blood meal, is as its name suggests, and made from blood that is gathered at slaughterhouses, then dried and powdered. Blood meal acts by adding nitrogen to the soil which then helps the bulbs to absorb more nutrients and other fertilizers to bigger and better blooms. Nitrogen, as discussed previously, also helps the bulbs to produce more foliage and leaves, giving them efficiency in absorbing more energy that they can store away to produce bigger and better blooms in the following year.

But there\’s always the saying which goes that too much of a good things isn\’t always great. Too much blood meal in the soil will provide the bulb with too much nitrogen, causing even little to no flowering. So how much blood meal should you add?

You should add about 2 – 3 pounds per 100 square feet on bulbs that you have already planted, as long as the foliage is not above ground yet. If you have not planted your bulbs yet, add about a teaspoon of blood meal for each bulb (into the hole you dig for your bulb). Mix the blood meal thoroughly with the dirt, then put the bulbs in to ensure an even distribution of blood meal in the soil.

Sprinkling some blood meal on your bulbs also helps deter squirrels and chipmunks from devouring them. Just remember though, it can also encourage digging from dogs and cats. It can also attract skunks and raccoons, encouraging them to dig up your bulbs which can be a nightmare. Test the usage of the blood meal in a small area in the garden before actually using it to find out how neighborhood animals react to it.

Tip: Get your supply of blood meal at the feed store (instead of a garden center) as it may be cheaper.

How to Apply Fertilizer?

Do not mix fertilizers directly into the planting hole with the bulb. Fertilizers should be applied as top dressing (on top the soil a few inches under) to avoid \’burning\’ the bulb or its roots. Direct contact with nitrogen in the fertilizer can kill plant tissue, causing root death and bulb failure.

The Netherlands Flower Bulb Information Center recommends mixing slow release bulb fertilizer into the top few inches of soil once a year. Fertilization should be done in fall when new roots are emerging from the bulbs which will absorb nutrients. If you are going to apply fertilizers over bulbs in spring, apply them just as the shoots emerge (after spring thaw). Do not fertilize bulbs when it is about to flower or too long after flowering. Top dress the soil with well rotted manure or compost yearly to provide your bulbs with that extra boost needed.

Note: Fertilizers work only is there is sufficient water available that acts as a medium for your plants to absorb the nutrients up the roots from the soil. So make sure you water the bulbs as soon as you plant them and throughout the growing season.

More Reading:


Gardenersgardening.com: http://www.gardenersgardening.com/flowerbulbs.html