How to increase size of Chrysanthemum flowers?

VijayWani

Hi,

I have Chrysanthemum plant purchased from bunnings but it is not blooming with big flowers. Almost 6 months its buds were not blooming. 2 months before they started blooming but the flowers are very small. The pot is always in sunlight. I am using Richgro Black Marvel Rose And Flower Food.

I need your advise for

1. What kind of ferttilizer  would be useful to get large flowers ?

2. How and when to prune the plant ?

EricL

Hello @VijayWani 

It sounds like your chrysanthemum is healthy enough to bloom, but it’s struggling to reach its full flowering potential. Small flowers after delayed blooming can often be linked to a few key issues: nutrient imbalance, pruning timing, and potting conditions. The good news is that with a few adjustments, you should be able to encourage bigger, more vibrant blooms in the next flowering cycle.

Richgro Black Marvel Rose & Flower Food is a good high-potash fertiliser, but chrysanthemums also benefit from a more balanced feeding schedule. 

A fertiliser with a balanced NPK ratio (such as Yates Thrive Flower & Fruit Soluble Fertiliser) is ideal in the lead-up to blooming, especially one that includes trace elements like magnesium and iron. Magnesium is especially important for flower size and colour, and a supplement like Epsom salts (magnesium sulfate) can be watered in monthly to help support bloom quality. You can continue using Black Marvel when buds are forming, but earlier in the growing season (late summer to early autumn), start with a more balanced fertiliser to support overall plant health and strong growth before switching to a bloom booster.

In terms of pruning, chrysanthemums benefit from regular pinching and post-flowering pruning. In early spring, when new growth starts, pinch off the tips of young stems to encourage bushier growth and more flowering stems. Do this a few times until early summer, but stop pinching by around late December to early January to allow flower buds to develop undisturbed. After the plant has finished flowering (usually in late autumn), you can cut it back quite hard—about two-thirds of the way down. This encourages fresh new shoots and resets the plant for the next growing cycle.

With consistent feeding, seasonal pruning, and fresh soil, your chrysanthemum should reward you with bigger, brighter blooms next season.

If you need further assistance, please let us know.

Eric