If you don't mow too early, fertilize on time and water in dry years, the bulbs will bloom more profusely each year. If you mow too early or there is too little moisture and nutrition, tulips, as well as eventually daffodils and crocuses, will soon bloom less profusely.

First the theory

the growth cycle of spring bloomers

The falling temperature in the fall, is the signal for the newly planted flower bulb to form roots. To do this, the plant uses some of the energy stored in the flower bulb. The roots formed absorb water and nutrients from the soil. After the winter dormancy period, the active growth phase starts due to the rising temperature. Both the reserves in the bulb and the supply from the roots allow rapid growth of leaves, stems and flowers. After flowering, the leaves remain green for a time, allowing photosynthesis for energy production. This energy is stored in the bulb or in new bulbs. As the leaves yellow, the bulb withdraws nutrients from the leaves, then goes into a dormant phase to prepare for the next year. Moral of the story: A growing period after flowering, determines the following year's success.

Mowing

at least 6 weeks after flowering

As a general rule, flower bulbs should not be mowed for at least six weeks after flowering. Earlier flowering species usually want to keep their leaves a little longer, while later flowering species sometimes want to keep their leaves a little shorter. If you wait until the leaves have turned yellow, then you have given the bulbs time to pull all the nutrients back into the bulb, and you will have the best start for the next flowering season.

Fertilize

During or shortly after flowering

Fertilize bulbs during or as soon as possible after flowering. This can be done with a regular NPK fertilizer 12-10-18, about 2 kilograms per 100 m2. Fertilization also promotes grass growth, so earlier fertilization may come at the expense of bloom visibility. Therefore, do not fertilize too early. Also, do not fertilize too long after flowering, as the plants are already heading toward their summer dormancy by then. Fertilizing along during planting For new plantings, we offer the option of adding fertilizer after planting. Already in the fall, as temperatures drop, the bulbs make roots and take advantage of this fertilizer application. The included fertilizer continues to work until the following summer, so there is no need to fertilize separately throughout the first year.

Watering

Only in dry years

If it is very dry during flowering and finishing, give 20 to 30 liters of water per m2 several times. In 2024, it does not seem necessary in most places. We have too much rather than too little moisture in the soil. But in recent years, we have experienced drought several times in the spring. In such years, the plant is less able to create a healthy, well-filled bulb for the following year. In an extreme case, the bulb goes into survival mode and does not produce a flower bud. It will then have a leaf-only cycle the following year.

Timing

What about the blends?

If you have a mixture with crocuses, daffodils and ornamental onions, the flowering season runs as long as four months or longer. The early bloomers, as mentioned earlier, keep their leaves longer, so you may mow them later and fertilize them later. This ties in nicely with the later blooming species in the mix. Late-flowering species such as Allium and Camassia tend to be taller and rise well above taller grasses. Fertilizing first half of April and mowing late (at least a month after the last bloom; when the last leaves are yellowing) fits well with the various species in a mixture. Especially with the mixtures, also keep an eye on making sure the soil does not dry out.