Introduction

It’s early autumn and I’m noticing the sun’s pattern lowering in the sky. In the warmth of my greenhouse, I’ve been harvesting the last of my tomatoes, which line my kitchen counters with fragrant anticipation of pizza sauce. A new season begins, and a new opportunity to nurture the soil presents itself.

While there’s a chill in the air, that doesn’t mean that I’m going to leave my soil bare once I’ve cleaned up my tomato plant debris. There’s still time to grow food, remediate the garden, and even add nutrients back into the soil. As gardeners, we just need to plan ahead a little in order to make the most of this time.

It’s important to know a little about what other plants are in the same family as tomatoes, so that you can rotate your crops for more sustainable garden health. Curious to learn more about crop-rotation? I’ve got a Crop Rotation Plan for you here.

But, if you’re looking for specific information about what I plant after tomatoes, read on. I’ll share with you the magic this chilly season can bring to your garden soil. There are so many possibilities to explore!

Suggested Crops for Post-Tomato Planting by Zone and Type

If you’re wondering what to plant after tomatoes, here are proven options that have worked for me in the past. Each option offers something a little different for the next growing season.

I’ve considered different growing zones and goals within each of these choices.

Plan Ahead Options

• beets
• turnips
• broccoli

If you plan ahead, you can sow some seeds in modules in August, and transplant those seedlings into your raised beds post tomato harvest.

In this way, you give your next batch of plants a bit of a head start, which is especially important now that the daylight hours are decreasing. These early preparations will be something you thank yourself for later as you harvest from your future garden.

Beets and turnips are fairly frost hardy if your temperatures aren’t consistently dipping below 20 degrees. If you’ don’t enjoy turnips, have you ever tried them after a frost? Try planting them in the fall and see if you like them after the cold has sweetened them up.

Opt for fast to mature broccoli varieties, like broccoli rabe or De Cicco. Your broccoli plants may benefit from a row cover, depending on your growing zone.

Cover Crops

• Hairy Vetch
• Daikon Radish

Cover crops are key in regenerative gardening. They help sequester carbon during the off-season, and help to smother weeds while building soil health. Cover crops are like a gift for next year’s garden, an offering of nutrients, organic matter, and a vibrant microbiome.

I know you are probably wanting to plant crops to eat. But, your soil microbiome needs to eat too! Before you dismiss this, let me tell you about why Hairy Vetch is my go-to when transitioning from tomato plants.

Hairy vetch is a favorite of mine because it combats tomato-specific soil diseases and pests while adding nitrogen to the soil. This past year, I experienced the benefits of this cover crop. I delighted in seeing nitrogen nodules form on the roots and watching as bees flocked to its purple flowers in the spring. The green material made an excellent mulch that I was able to chop and drop around my plants, too.

While you can read more specific details about hairy vetch, here’s a recap of the scientifically-proven benefits of this cover crop for solanaceous crops like tomatoes:

• Prevents blight in tomatoes, disrupting that disease cycle if you can’t do a full 4-year crop family rotation
• Reduces potato beetle populations naturally
• Attracts beneficial insects that are predators to aphids, thrips, whiteflies, and mites for organic pest control (SARE, UC IPM)

For a few seasons, I planted daikon radish in my greenhouse after the tomato crop. I remember the first season after we did this - the difference in the soil was incredible! What was once hard clay soil that resisted any digging was now a lot softer and easier to work with. After repeated winters of daikon, the greenhouse soil is in much better condition.

Over-Wintering Plants

• Garlic
• Fava Beans
• Egyptian Walking or Multiplier Onions
• Leeks

Since tomatoes are usually harvested pretty late in the growing season, consider planting crops that can be sown in the autumn for a spring or early summer harvest. I love the feeling of walking by these crops, quiet below the surface, during the depth of winter. To know that something is growing in the soil still is very satisfying.

These plants are in the allium family (garlic, onions, leeks) or are legumes (fava beans), so they follow crop rotation best practices after tomatoes.

Right after clearing out a tomato bed, fava beans and leeks are a nice choice for areas with mild winters. They are successful overwintering crops in zones 7+ for a summer harvest. While they will grow slowly, the reward of a harvest next summer is totally worth it!

Favas not only grow quickly but also replenish nitrogen levels in the soil. I have an article that details the process that beans and soil microbes use to create nitrogen nodules - it’s fascinating!

If you have colder winters, garlic or egyptian walking onions are a great choice to sow after your tomato crop is harvested. Did you know that both of these crops actually benefit from the cold of the winter, which triggers its germination to happen? Just cover them with a nice organic straw mulch, or collect fallen leaves to keep the soil warm and protected.

Leafy Greens

• Bok Choy
• Spinach
• Kale
• Chard

Craving fresh greens in the fall? In many climates, it’s not too late to plant a crop of quick-growing leafy greens. Even as the leaves on the trees fall and other plants are starting to die back, these plants can offer a splash of color to your garden to brighten it up even in the dull of winter.

In colder zones, a simple row cover will help to extend your growing season. Hardy greens like kale and chard will be good choices if you have a lot of frosts. I am usually able to harvest from this pair until December or beyond!

Compared to tomatoes, leafy greens have different nutrient needs and don't deplete the soil as much. They’ll add some freshness to your meals throughout the fall.

Cold Stratification Scatter Garden

If you’re within a week or two of your first frost, you can try a bit of chaos gardening with veggies that need a period of cold in order to germinate and thrive.

You’ll essentially be replicating nature - sowing the seeds now, letting the cold awaken the seeds, and then you’ll have a bed full of new seedlings in the spring!

Great options for a late-summer flower scatter garden:

• poppies (annual)
• echinacea (biennial)
• hollyhocks (biennial)
• nigella (annual)

For more on cold stratification, I’ve got a full list of flowers, herbs, and veggies that need cold in order to germinate.

Additional Tips Based on Growing Zone:

• For Zones 1-2, a planting of garlic might work, but you may also wish to mulch your soil heavily to keep it covered until spring.
• For Zones 3-4, garlic or a daikon radish cover crop will work well post-tomatoes for zones 3+4.
• For Zones 5-6, try to grow some leafy greens under a row cover after your tomato harvest, or go for a garlic planting.
• For Zones 7-8, fava beans and cover crops will thrive when fall planted, and the timing lines up perfectly with the end of tomato season.
• For Zones 9-10 and 11-12, take advantage of the cooler fall temperatures in the autumn to plant a second round of leafy greens and root crops after you harvest tomatoes.

What NOT to plant after tomatoes

• Peppers, eggplants, potatoes: While it’s hard if you have a greenhouse or limited garden space, crop rotation with any vegetable in the Solanaceae family is something to think about, especially if your tomatoes had disease like blight.
  
  If you can, try to plant something from a different family in this spot in the upcoming years.
  
  On a related note, here’s how I’ve figured out crop rotation with tomatoes in my greenhouse.

• Lettuces: While your results may vary, it’s good to know that tomato plants have a negative allelopathic effect on lettuce seed germination. This study found that lettuce interplanted with tomatoes had a lower rate of successful growth. However, this study is with interplanting, and didn’t look at lettuce grown after tomatoes.

In  my experience, I’ve interplanted lettuces with tomatoes and after a tomato harvest, and both times did not notice any negative germination effects. This might be because I scattered the lettuce seeds heavily, so a lower sprouting rate wasn’t an issue.

Personal Experiences and Tips

Usually, cover crops are my first choice for what to plant after tomatoes. I’ve seen how hairy vetch works with soil microbes to develop nitrogen nodules on its roots, which is a great way to restore nutrients into the soil after the demands of tomatoes.

For a few seasons, I grew daikon after tomatoes, which really improved the soil structure in my heavy clay garden. What was once land that was tough to dig into is now loamy and a lot more conducive to planting.

I do like to harvest edible crops from the garden for as long as possible, too. Sowing some crops like beets, leeks, and turnips in modules has really helped me to extend the growing season so that I actually get a harvest from these crops, which otherwise would really slow their growth rates with less daylight hours.

I’ve found that if I direct sow beets after I clear out my tomatoes, even in the greenhouse, the harvest from them is pretty small.

Practical Tips for Success

1. Timing: Start plants ahead of time in modules, or sow hardy plants right after you clear out your tomato bed for best results.
2. Clean all residue: Normally, I’m all about chop-and-drop and leaving roots behind in the ground. But tomatoes are so prone to disease that I have a separate compost pile for them in my yard so as not to perpetuate any harmful microbes in my soil down the line.
3. Soil Preparation: Replenish the soil with some compost, leaf mold, or broken-down chicken manure to help the next crop thrive.
4. Cold Protection: Mulch around plants once they’ve germinated in order to keep the soil warm. If necessary, use a row cover to protect crops from frosty temperatures.

Supporting Soil Health After Tomatoes

Once your follow-on plants have grown to around 3 inches, mulch around them with weed-free grass clippings, fallen leaves, or organic straw to help keep soil warm.

Some composted chicken manure will also help build soil health and add some nutrients to the soil.

What are you planting after your tomato harvest?

Gardening is a journey of learning and experimenting. By thoughtfully planning what to plant after onions, you’ll not only enjoy a bountiful harvest but also contribute to a thriving garden ecosystem.

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