How to Plant & Grow


Affordable, fun, and half-hardy - that’s right, we’re talking about zinnias. These attractive annuals are easy to grow, when you know how.  

Here are our top tips for growing zinnias from modules and seeds for a superb summer display. 

What We’ve Included 

When to Plant  |  How to Plant  |  Where to Plant  |  Feeding Zinnias  |  After Care  |  When do they Flower?  |  Inspiration

When to Plant Zinnias 

Seeds can be sown indoors from March to April. You can sow seeds directly outside from May to June, along with plants and modules.

How to Plant Zinnias   

Planting Zinnias Modules & Pots   
Our modules and pots are incredibly easy to plant and maintain. Whether you’re growing them directly outside into the border or in a container or keeping them indoors over winter, our modules are a breeze to care for from the moment they arrive.  

- Dig a hole in the border that’s big enough to house the entire module. If planting in pots, fill a large pot halfway with potting soil and then make several holes that can hold the modules. Do this until the top of the soil from the module is just below the top of the pot.   
- Fill around the modules with soil and firm them down gently.    
- Water well and you’re done!

Planting Zinnia Seeds 
 Zinnia seeds can be sown indoors from March to April. They should take roughly 4-6 weeks to grow seedlings. Sow in small modules, covering them lightly with soil and keep moist.  
Can be sown directly outdoors from May to July, once the threat of frost has passed. When large enough to handle, thin and transplant into trays, and growing them on under cooler conditions.  
Pinch back seedlings to their first set of leaves. Once the seedlings are large enough (when growing them indoors), plant them outside once the threat of frost has passed. 

Where to Plant Zinnias 

Zinnias love a well-drained but sunny spot. Provide partial shade for optimum results.

Feeding Zinnia

Zinnias can benefit from regular feeding throughout the season. A liquid feed will work best for this, or you can apply slow-releasing fertiliser when planting if you prefer a low-maintenance option. 

After Care

When to water Zinnias
Water zinnias in hot weather. Avoid getting their foliage wet, as it can cause fungal diseases to develop. 
Deadheading Zinnias
Deadhead spent flowers to keep your display looking tidy and to encourage further flowering. 

Common Issues and How to Solve Them  

Zinnias are fairly pest free, although you may have an issue with slugs attacking your seedlings. In cold and damp weather, zinnias can contract fungal diseases. Ensure they’re not sitting in overly wet conditions to mitigate this. 

When do Zinnias flower?   

Most Zinnias will flower between July and October. This may differ depending on the type you have purchased but do be extra sure, you can see their flowering months on their online product pages.    

Ready to Shop?

Find some inspiration for your garden