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Can You Plant Dianthus With Tomatoes? 

Can You Plant Dianthus With Tomatoes? 

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Willie Moore
Latest posts by Willie Moore (see all)

Growing fresh produce with flowering plants in the same bed or site is a great way to use a small gardening space. However, when choosing the right plants to pair with tomatoes, you must ensure they share similar requirements. So, can you plant dianthus with tomatoes?

You can plant dianthus with tomatoes. These plants have similar requirements, such as sunny conditions, in order to grow. This makes it easier to care for the plants while ensuring they both thrive.

In this article, I’ll look at what to know about growing dianthus with tomatoes to ensure the success of both types of plants. I’ll also feature both plants’ requirements and tips for planting success. 

Does Dianthus Do Well With Tomatoes?

Dianthus does well when planted with tomatoes because it isn’t a plant that’s a heavy feeder. Since it doesn’t require a lot of nutrients, it won’t compete with tomato plants for resources. Dianthus also deters deer, which can attack tomato plants.

If you’re sick and tired of seeing your tomato leaves and fruit being eaten by deer in the region, you should plant dianthus closer to your tomato plants. One of the biggest advantages dianthus has for tomato plants is that it deters deer because its leaves taste bitter to these animals. 

Dianthus is a perennial flowering plant that displays fringed flower petals and blooms in a variety of colors. Although quite different in appearance from tomato plants, it has many of the same requirements as tomato plants, which is why it’s such a great companion plant for it. 

Here’s a rundown of what requirements dianthus and tomato plants have: 

Light Requirements

Both dianthus and tomato plants want to be in full-sun conditions as they thrive in the warmth. Their requirements are exactly the same, with both plants wanting to be planted in an area of the garden that receives at least six hours of sunlight daily. 

This allows you to plant them together in the same area of the garden without worrying that one of them will struggle to survive. 

Water Requirements 

Although tomatoes want a lot of water, this doesn’t mean their soil should be wet or drenched, as this can cause the plants to struggle to grow. When you first plant tomato plants in the garden, they need moist soil. But then, as the plants become established, they need about one inch (2.54 cm) of water every week. 

Similarly, dianthus requires one inch (2.54 cm) of water every week. It doesn’t want to sit in water, so avoid waterlogged soil. When first planted, make sure you give your dianthus seeds enough water to keep their soil moist. This will enable them to germinate.

Since dianthus is a perennial, you want to water it weekly to allow the roots to grow deep into the ground without being flooded. 

Soil Requirements 

Dianthus plants fare terribly in clay soil, so if your soil contains a lot of clay, you should plant them in raised beds instead. These flowering plants want sandy soil with sharp drainage. When it comes to soil pH, choose slightly alkaline to neutral soil, which is a pH of 7.0.

Tomatoes want a soil pH of between 5.8 to 7.0, so these plants can share the same soil with dianthus. To ensure you provide tomato plants with the correct type of soil, make sure you plant them in sandy loam soil that drains well, so their roots are not waterlogged. 

Temperature Requirements

Both dianthus and tomato plants struggle when the temperature dips lower than 40°F (4.4°C).

When it comes to high levels of heat, dianthus doesn’t perform well when temperatures are very hot and humid. If temperatures soar higher than 85°F (29.4°C), the plant’s flowers will become dormant. Therefore, you’ll have to protect the plants from extreme heat in the summer months, such as with a shade cloth.

As for tomatoes, although they like warm conditions, you don’t want to expose them to daily temperatures that are higher than 85°F (29.4°C). When exposed to this extreme heat, the tomato plants’ flowers will drop off the plant (source).

Therefore, make sure the planting site for your tomatoes and dianthus has temperatures between 40°F to 85°F (4.4-29.4°C) for best results.  

Fertilizer Requirements 

Both tomato and dianthus plants have similar food requirements. While they appreciate a bit of fertilizer, they don’t want too much of it.

Dianthus wants to be fed fertilizer every two months during its growing season. I’d recommend feeding it BioAdvanced Rose & Flower Care (link to Amazon). This is a plant food and insect killer in one. It keeps diseases such as fungal infections at bay. 

In comparison, tomato plants want to be given a light fertilizer every two weeks after they display fruit. I’d recommend a fertilizer such as Miracle-Gro Plant Food (link to Amazon). It contains natural ingredients to strengthen plants and encourage them to produce more fruits. 

Things To Consider When Planting Dianthus With Tomatoes 

Although dianthus and tomatoes can be successfully planted together in the garden, there are some important things to bear in mind, such as when it comes to their spacing requirements. Here are things to consider:

  • Give tomato plants more space. While dianthus plants need to be planted about six to 12 inches (15.24-30.48 cm) apart, tomatoes want between 18 and 24 inches (45.72-60.96 cm) of space. Consider this when planting them in the same site or raised garden bed.
  • Don’t give dianthus humidity. Too much humidity can cause the plants to struggle to grow, but encouraging better air circulation can counteract its effects. In comparison, tomato plants want between 65% and 85% humidity. 

Final Thoughts 

It’s a good idea to grow dianthus and tomatoes together. Both of these plants want similar growing conditions, meaning you can do less to enable them both to thrive. Both dianthus and tomato plants want:

  • Full-sun conditions
  • One inch (2.54 cm) of water per week
  • Fertilizer every few weeks
  • Lack of shade
  • Temperatures higher than 40° F (4.4°C)

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