Optimum Conditions Means Faster Flowering

The way to fast-track flowers is to give them optimum growing conditions.

Many plants can be encouraged to produce their flowers earlier in the growing season and for longer periods of time. Here are some of the techniques you can use to get flowers to open sooner.

Many plants won’t flower if they don’t have enough light. Other plants need certain types of light before flowering can take place. You also need to know what the seeds need to germinate - whether a particular variety needs light to germinate, or darkness. A plant's response to light is scientifically called the 'phototropism response'. Check you have measured the plants needs for light levels and whether it grows best in sunny or semi-shaded conditions - it might be a plant variety native to shaded woodlands, or it could be native to sunny desert regions where it is bright, hot and fairly dry over the growing season.

Flower buds will form on many plants in response to a certain set of temperature conditions or, in some cases, a combination of temperature and other conditions. If a winter is not cold enough then some plants (e.g. apples, peaches, plums, cherries, flowering quince) may not flower as well in the following spring. Similarly, some bulbs such as tulips and some species of crocus may not flower if they do not go through an adequate period of cold chill following warm weather. The majority of annuals however, can be grouped into warm season or cool season plants so the plant response will be according to this and the time you plant them.

Most plants will not flower if the soil quality is poor. Good drainage, nutrition, lack or presence of toxins and adequate moisture are all important. The best quality soil mix or soil preparation (if you are sowing seeds in the open garden beds) generally gives the best results. Mixing well-decomposed compost and animal manures into the soil will add fibre, help to open up the soil to let air and water penetrate, and add some nutrients at the same time. The fibre from manure will also encourage worm activity and help the soil to hold moisture more efficiently when conditions are dry.

Do not use fresh manure unless you are preparing the soil and then going to leave it subject to rain and weather conditions for several weeks, otherwise fresh manure can burn seed as it tries to germinate and burn through the stem of young seedlings. Placed thickly on the bed it can also build up a great deal of heat as it decomposes, which may also affect young plants.

If the fertiliser used contains too much nitrogen, plants will be encouraged to put on leaf growth, but flowering is deterred - perhaps until the end of the season, or maybe not at all - before the plant withers.

Feeding plants with potash, or a fertiliser containing potash and phosphorus as well as nitrogen, will often encourage better flowering. There are fertiliser mixes available from nurseries that are balanced and composed especially for flowering plants and a quality mix will contain a mix of fast and slow release nutrients.

Regular feeding with a liquid fertiliser will also help flowering particularly in container plants. Rotate several types of liquid fertilisers in your fertilising program for the best results.

For pot plants, use a quality potting mix specifically formulated for the type of plant you are growing e.g. orchid mix contains lots of bark and is very free-draining. Terracotta mix, container mix, hanging basket mix, or something similar are the types to choose for fast-growing, hungry annuals.

Any shock such as a rapid change in water around the roots (too much or too little), can cause flower buds to drop off many types of plants.

Make sure you water the plants carefully with fine roses and sprinkler heads and at the right time of the day so the flowers are refreshed. Heavy watering from overhead sprinklers or a tropical downpour can damage flowers and buds as well as young stems.

Water sitting on young tender flower buds, especially during hot sunny weather or if they are in a heated glasshouse, will make them susceptible to fungal diseases. Similarly, the tender petals of flowers on Violas (Pansies), Primula hybrids (Polyanthus), and other soft annuals planted out in late winter are damaged by heavy watering, heavy rain, or frosts and tend to develop moulds and rots. Other plants with soft foliage or leaves covered by hairs can be susceptible to rotting particularly in warmer weather. It is often best to avoid getting water on the foliage and flower buds wherever possible.

Drip irrigation, mulching or flooding the surface of the ground may encourage faster and better flowering. Watering late at night or early in the morning allows moisture from overhead systems time to evaporate off plants before conditions warm up.
Read more on Growing and Knowing Annuals in our ebook.
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