15 Tips For Growing Great Garden Tomatoes
Growing tomatoes can be a bit intimidating for both seasoned gardeners and beginners. While their yields can be bountiful, they can also bring problems to your garden as well. In this article, gardening expert and homesteader Merideth Cohrs shares 15 of her top tips for fantastic garden grown tomatoes this season!
If you have decided to take the time to grow tomatoes this season, I’m pretty sure that you want to maximize your harvest and ensure it’s as flavorful as possible! We all know the neighborhood gardener who seems to grow the most gorgeous tomato plants and harvests enough fruit to eat, share, and can.
We also know the gardener who winds up with only a few sad looking tomatoes each year. Personally I always try to be the person with so many tomatoes that I’m literally sick of looking at them by the end of the growing season.
But harvesting a very large tomato yield means that I did a lot of things right during the growing season. Let’s take a look at some of my top tomato growing tips to ensure your harvest is as bountiful as it can be!
- 1 Choose a Variety You Love to Eat
- 2 Growing From Seed vs. Transplants
- 3 Don’t Plant Too Early
- 4 Choose a Location with Full Sun
- 5 Give Them Plenty of Room
- 6 Pick The Right Soil
- 7 Feed Them All Season
- 8 Water Correctly & Don’t Overwater
- 9 Always Companion Plant
- 10 Encourage Pollination For More Fruit
- 11 Know When and How to Prune
- 12 Give Your Plants Support
- 13 Mulch Your Plants
- 14 Check For Problems Daily
- 15 Pick Fruit Early and Often
- 16 Final Thoughts
Choose a Variety You Love to Eat
Choosing the right tomato variety is all about identifying how you like to eat them. You can grow beefsteak varieties for slicing (perhaps with fresh mozzarella and basil!) and sandwiches, saucing varieties like Romas and San Marzanos, or sweet cherry tomatoes that you pop right off the vine and into your mouth!
If you are picking up seedlings from the nursery or your local garden center, you’re kind of at the mercy of what they happen to be selling. The good news is that since tomatoes are so popular, there are generally a good amount of options available.
If you’re not super familiar with what kind of tomato you want, don’t hesitate to ask one of the garden associates. They can give you a few recommendations based on your preference.
If you’re interested in starting your tomatoes from seed this season, the sky is really the limit as to what’s available to you. Online seed catalogs completely opened up the world of seed starting.
They contain a huge selection of tomato varieties including cherry, grape, plum, cocktail, beefsteak, paste, and heirlooms. You can find indeterminate or determinate varieties of each of those, and choose from fruits that range in color from red, green, yellow, orange, purple, and striped!
Growing From Seed vs. Transplants
When you’ve decided on the right variety, next up comes deciding if you’ll grow from seed, or if you’ll buy starts from a local nursery that you can transplant into your garden. Let’s take a look at why each of these growing methods can be successful, and which one I prefer.
Personally, I grow my tomatoes from seed each year. This allows me to choose seeds that I know grow well in my area, have great flavor, and are organic and non-GMO. I can also be confident that my seedlings are healthy, vigorous, and well hardened off prior to transplanting outside.
Burpee, Baker, and TomatoFest are great places to start looking at seeds, but there are a lot of options out there. Be sure to read reviews, and see how other gardeners have fared with the varieties you’re interested in.
I have had great experiences with seeds that other gardeners have done well with. And I have had sad germination rates with seeds that had no reviews. Gardeners are a friendly lot and typically want to share information whenever they can. Pay attention to them especially if you’re a newer gardener!
I recommend buying vegetable starts from a local nursery or farmer’s market over a big-box store whenever possible. Seedlings there are typically sourced from local or regional growers, are grown organically, and are well cared for.
Often, starts at your local big-box garden center are treated heavily with pesticides and they are shipped quite a distance from non-organic growers. Some retailers have phased out neonic pesticides (which kill bees and other pollinators), but not all.
Regardless of where you buy your seedlings, take the time and choose the healthiest ones. The plant should have dark green leaves, be well branched, shouldn’t be leggy (meaning it’s too tall for the stem to support it well), and shouldn’t have flowers yet. Avoid tomato plants with yellowing leaves, strange growth patterns, and flowers.
The general rule of thumb for planting warm season crops like tomatoes, is that plants can be transplanted outside once they have been hardened off and you are two weeks past the last frost date of your area.
With that said, every area has its quirks. Where I live in northern VA, we experience volatile springs. We may have a week or two of temperatures in the 70s or low 80s, but then have another 3 weeks of temperatures in the 50s. Because of this, gardeners in my area wait until Mother’s Day to plant tomatoes and other warm weather crops even though we’re technically far past our frost date.
If you’re unsure when to plant in your area, join a local gardening group and ask! Local gardeners are more than happy to help, especially when it may save you from a lot of heartaches.
Just remember that tomatoes like to be outside once nighttime temperatures are consistently above 55 degrees. If you plant them too early, they will not grow well.
Location, location, location. At a minimum, tomatoes need to be planted in an area that receives full sun, meaning 6 or more hours of direct sun each day. Southern exposure is ideal, where they receive light during the majority of the day but are protected from the strongest afternoon sun. Tomatoes will do just fine with western exposure (where the majority of sunlight starts afternoon) as well.
Anything less than 6 hours of direct sun is considered partial shade. If you plant your tomatoes in an area with this level of sun exposure, they won’t grow as well and will likely produce less fruit.
Ideally, try to plant your tomato plants in a location where they receive 8 hours of direct sun each day and have some protection from the harshest afternoon sun. Remember, the more sun your tomatoes get, the more flowers will form, the more fruit will set, and the sweeter the fruit will be!
Give Them Plenty of Room
Tomatoes like their space. Well spaced tomato plants will reward you with healthy, disease free foliage and delicious tomatoes. On the other hand, if you plant them too closely together, your tomatoes can be more vulnerable to pests and disease.
I am definitely guilty of trying to squeeze a few extra plants into my small gardening space. It’s so tempting when your seedlings are small! But remember that your tiny seedlings will grow into very large plants that are nutrient hungry and sun-loving.
Let’s talk about airflow. Airflow is really important to the overall health of your tomatoes. This is why we talk about pruning the lower branches of tomatoes; it increases the airflow at the base of the plant. Densely planted tomatoes have an obvious problem with air circulation, which can lead to conditions that attract pests and disease.
Tomatoes are also incredibly nutrient hungry, which is why you need to fertilize them consistently throughout the growing season. Too many tomato plants in a small area will create conditions where the plants are competing for limited resources. This can cause nutrient imbalances, stunted growth, and poor fruit production.
Lastly, your tomatoes need lots of sun! If they’re planted too closely together, some plants may actually wind up in partial shade conditions, which will impact growth, flower development, and fruit yield.
A good rule of thumb is to leave 30-46” between each seedling when transplanting outside.
Pick The Right Soil
Tomatoes are heavy feeders and require an organically rich, fertile, well draining soil to thrive. If you are using raised beds or containers, choose a well-draining potting soil and add organic material at the time of planting.
If you’re planting directly in the ground, you will likely need to amend your soil ahead of time. Make sure you aerate the soil around and under your planting site (this will prevent soil compaction) and amend it with rich organic material or compost.
Good drainage is also very important to tomatoes. They like it when soil can begin to dry out between waterings. If you struggle with heavy clay soil like I do, you will need to add amendments to improve drainage. Coconut coir is an excellent choice for this since it improves airflow even when wet, lightens heavy clay, and aids in moisture retention.
Your tomatoes will thrive in slightly acidic soil. Ideally, you want your soil to have a pH between 6.2-6.8. You can buy a pH testing kit to check the current acidity of your soil. If it’s not quite where you want it, you can add a soil acidifier prior to planting.
Tomatoes are unique because the plant can grow roots from any part of its stem that is buried underground. Trimming off the bottom sets of leaves prior to transplanting outside will allow you to deeply bury your tomatoes and encourage them to grow a deeper and more dynamic root system.
I always trim off at least one set of leaves to allow me to bury the plant a little deeper in the ground. Feel free to trim off 1-3 sets of leaves as long as you leave 2-3 sets of leaves above ground.
Once the plant is as deep as you want it, cover the root ball with soil and gently press down with your fingers. Add mulch around the base of the plant to help it retain moisture and then water deeply.
It’s a good rule of thumb to keep your newly transplanted tomatoes well-watered for the first week after planting. This will help the plant settle in and encourage root expansion into the new soil.
Feed Them All Season
Now that we know how to prepare our soil for planting, let’s talk about fertilization. As a new gardener, this is something I didn’t pay any attention to, and I was disappointed in my early harvests. But now we know that tomatoes are nutrient hungry; let’s talk about how to feed them correctly.
Choosing the correct fertilizer for different stages of tomato growth deserves an entire article on its own. But, in general, tomato-specific fertilizers will have a certain balance of macronutrients like nitrogen, phosphorus, and potassium, and micronutrients like magnesium, calcium,and zinc.
Here’s a little cheat sheet on the macros you find in fertilizer:
Promotes foliage growth. Too much will lead to very bushy plants with little to no fruit.
Crucial for the growth and development of roots as well as fruit. Very important in both the initial stage of growth as well as the final stage of fruiting.
Helps the plant grow rapidly and produce flowers and fruit. Also important to efficient photosynthesis and tolerance for some diseases.
You can see from this list that your tomatoes need certain macros more at various stages of growth. There is sadly no single tomato fertilizer that works best for all gardens at all stages of growth.
When first planting your tomatoes, a balanced (10-10-10) slow release fertilizer is the ideal choice. But once the plant has reached maturity, starts flowering, and produces fruit, a fertilizer higher in phosphorus and potassium (5-10-10) is recommended. This will help the plant produce more flowers and direct its energy into turning those flowers into fruit.
Water Correctly & Don’t Overwater
There’s no doubt about it, tomatoes are pretty fussy when it comes to getting the right amount of water. Too little and the plant won’t thrive; too much and you’ll damage the roots, causing the plant to not thrive. You get the idea… When it comes to watering, we truly are looking for a ‘goldilocks’ situation.
A general rule of thumb is to water your tomatoes about 2” a week for a plant in the ground (more if your tomatoes are planted in containers). But environmental factors like wind, heat, humidity, rain, and soil type can all play a role in adjusting that number up or down. The age of your plant and the stage it’s in also makes a big difference in how much water it needs.
My recommendation is to get a feel for the dryness of your soil. Only water once the top layer – the soil you can feel with your index finger (about 1-2 inches down) – has dried out. This will prevent any danger of over- or underwatering that tends to arise when you try to water on a set schedule. The bottom line is to only water your tomatoes when they need it!
Your tomatoes need a regular and consistent amount of water to thrive and produce as much fruit as possible. You won’t do your plants any favors if you quickly flood the soil every few days and call it done. This is the equivalent of you drinking from an open fire hydrant. You’ll get some water, yes, but you likely won’t be satisfied.
Ideally, you can set up a drip system in your garden. Turn it on in the morning for a few hours and happily go about the rest of your day. If a drip system isn’t possible, or if you’re planting in containers, use a slow flow hose. This will allow you to deeply water your plants without creating unnecessary runoff.
No matter how you water your tomatoes, be sure to do so at the base of the plant. One of the biggest mistakes new gardeners make is to water the leaves. This can cause several problems including pest attraction, leaf burning, and disease. Instead, focus your watering on the soil around the plant so the roots receive the water they need.
- Only water in the mornings and try to avoid wetting the leaves.
- This will help minimize problems with disease and leaf burn.
- Water your tomatoes less once fruit begins to set.
- Watering too much at this stage can cause the fruit to crack.
- Your fruit will also be sweeter with less water!
Always Companion Plant
I love to talk about companion planting! And I truly believe that the addition of herbs and certain flowers in your vegetable garden can add very tangible benefits to your tomato plants.
Did you know that your garden is its own mini-eco system? It is! The more plants, (good) bugs, and animals that are in your garden, the more resilient it will be. If you choose to garden organically, this biodiversity is incredibly important.
Certain herbs and flowers encourage stronger growth for your tomatoes, others repel or ‘trap’ pests, and others attract a host of pollinators and predatory insects. In fact, companion planting can also help with sun management, soil health, weed control, higher yield, and tastier fruit. Here are a few of my favorite companion plants for tomatoes:
Basil and tomatoes are a natural pairing in food and in the garden. It can help deter certain pests like whiteflies, thrips, tomato hornworms, and aphids. But the real benefit to planting basil with your tomatoes is the flavor.
Many gardeners say that their tomatoes are always sweeter when planted near basil. This is a companion plant I choose each season in my own garden
Another one of my favorites, the sulfur compounds deter aphids and the plants come back year after year. They not only improve the flavor of tomatoes planted nearby, they’re a great addition to your cooking wherever a light onion flavor is needed.
Lettuce is probably the most unconventional companion plant in this list, but I love to plant leafy greens with my tomatoes. This pairing has nothing to do with pest control or plant health, but it will protect the soil around your tomatoes and improve biodiversity in your garden.
As a cooler season crop, lettuce needs shade to grow in the hot summer months. The shade provided by your tall tomato plants is ideal. In return, lettuce plants will keep the soil around your tomatoes cool and moist.
Nasturtiums are an excellent sacrificial ‘trap plant’. Their natural peppery fragrance really attracts certain pests like aphids and whiteflies. Instead of infesting your core tomato plants, these pests will feast on the flowers!
Once you note that a plant is heavily infested, just remove and dispose of it (do not compost). Nasturtiums also attract a host of predatory insects that can also help keep pest populations down.
These flowers can also be instrumental in warding off fungal diseases. Because they make excellent ground cover, nasturtiums prevent water from splashing back on the low-hanging tomato and pepper leaves. This prevents fungal diseases spreading from the soil to your vegetables.
In addition to attracting pollinators and predatory insects, marigolds do a great job at deterring certain problematic pests. The flowers secrete a chemical compound called limonene that specifically deters whiteflies and aphids.
Marigolds are also fantastic at reducing harmful nematode populations. They produce compounds in their roots called alpha-terthienyl that seep from the roots into the surrounding soil. Over a 3-4 month period, this toxin can kill nematodes and deter any new infestations.
Marigolds will be most effective at reducing nematode populations and deterring pests like aphids and whiteflies when planted closely together. They will also need time to mature enough to actually be capable of producing the chemicals previously referenced.
If you know you have a nematode problem, consider planting clusters of marigolds in problem areas early in the season.
Encourage Pollination For More Fruit
While tomatoes are self-pollinating, you can help the process along to maximize fruit production. It seems a little silly at first, but all you have to do is gently shake your plant or tap flowering branches to help move the pollen.
High temperature and high humidity can all have a negative impact on the pollination process. Humidity can cause pollen to become sticky and prevent it from falling off the flowers. In dry regions, the pollen can actually dry out and fail to stick to the female parts of the flowers. By helping the plant self-pollinate, you’ll improve your tomato yield this season!
Like watering, tomato pruning is another goldilocks area when it comes to tomatoes. Pruning stresses out your plant, but it’s essential for keeping it healthy and growing efficiently (although there are some gardeners who firmly believe pruning of any kind does more harm than good).
No matter which side of the pruning debate you fall on, everyone agrees that excessive pruning is a bad idea. It can cause a number of problems including yellowing or curling leaves, stunted growth, and a decrease in fruit production.
Pruning Tips for Determinate Tomatoes
As the name suggests, determinate tomatoes grow to a determined size and produce a determined amount of fruit. Pruning these types of tomatoes can have a negative impact on fruit production.
Before the plant sets its first flower, you can prune off the bottom-most branches that may be touching the soil. Leaf contact with the soil – either directly or through water splashing back on the underside of leaves – can cause a number of fungal diseases.
This will improve air circulation underneath the plant. But no matter what, do not prune determinate tomatoes AT ALL once the first flower appears.
Pruning Tips for Indeterminate Tomatoes
Indeterminate tomatoes benefit greatly from gentle pruning throughout its growth cycle. You’ve probably heard of pinching off suckers…
This is simply the removal of new growth between the primary and lateral stems of your tomato. This forces your tomato plant to put its energy into the main growth lines rather than creating a lot of branches that won’t ever produce fruit. Limiting each plant to 2-5 primary stems will help it maximize fruit production.
Indeterminate varieties will also benefit from the removal of the lower branches to improve air circulation and prevent soil splash back.
Give Your Plants Support
You may not know this, but tomato plants will grow happily along the ground if you let them. Unfortunately, this can invite fungal disease, give pests and rodents easy access to the fruit, and doesn’t encourage the plant to maximize fruit yield. So, gardeners have long trained their tomato plants to grow vertically by staking or caging.
Supporting your tomatoes properly requires stake, cages, and ties. It’s a good idea to install both the stakes and cages at the time of transplanting so the root structure isn’t bothered by installing later on. For the ties, choose something that isn’t going to cut into the tomato vine. You can purchase plastic ties to reuse each season, or reuse items in your house like old shirts cut into thin strips.
Attach the tomato vine to the stake with a loose tie every 6-8” as the plant grows. Always place your tie above flowering stems so it doesn’t cut into the stem after it’s weighted down with fruit.
You will find that determinate varieties are much easier to stake and cage. Indeterminate varieties will keep growing as long as conditions are good. I usually let the top of my indeterminates droop down after they get too tall and then tie them to the upper portions of my cages. You can also use a tall trellis or fence depending on where your tomatoes are planted.
Mulch is incredibly important to your tomatoes. Mulch provides protection against excessive heat, helps the soil retain moisture, prevents water splash back (which can spread fungal disease), and discourages weeds.
You can use a lot of organic materials as mulch. Straw, grass clippings, wood chips, and crushed up leaves are all things you can repurpose from your yard (if it hasn’t been treated with herbicide/pesticide).
You can also use mulch purchased from your local nursery or garden center. Personally, I love to use coconut coir as mulch. You can purchase mulch blocks that just need a soak in water prior to use. No matter what type of mulch you choose, aim to apply a layer 2-3” thick for maximum benefit.
Check For Problems Daily
Pests, disease, yellowing or curling leaves, nutrient deficiency, blossom end rot… These are just a few of the things you need to be mindful of when growing tomatoes.
It’s far easier to fix a problem if you can catch it early. Many pests, for example, are easy to eradicate if you notice them early on, but a full infestation can be incredibly problematic. The same is true of disease. Some diseases are completely reversible if caught in the beginning stages, but can be fatal to a plant if left unchecked.
A good rule of thumb is to spend time in your garden each day, even if it’s only for a little bit. Take a look at your tomato plants, check under the leaves for small pests like aphids and spider mites, look for signs of stress or damage, and always be on the lookout for bigger pests like tomato hornworms that can destroy a plant in a matter of days.
Picking those first ripe tomatoes off the vine is one of my favorite parts of summer. But did you know that picking the first tomatoes a little early can convince the plant to make even more fruit?
It does! Picking early fruit as soon as they’re formed (even before they are ripe) tells the plant that it needs to get more productive. Some gardners take this a step further and pick off the entire first cluster of flowers. I’m not sure I’m brave enough to try that, but picking the first fruit early really does make a difference!
After you pick those first unripe fruits, it’s ok to let your tomatoes start to blush a bit before picking. But if you want to maximize your harvest this season, pick fruit at the first signs of blushing and place them near a sunny window to continue to ripen. I promise that the fruit will be just as sweet as if you picked it fully red and juicy from the vine.
PIcking this way does a few things. It protects ripening tomatoes from birds, squirrels, and stink bugs, but also tells the plant that its job isn’t done yet. Remember, fruit is the way tomato plants try to create more tomato plants.
In nature, this is only accomplished when ripe fruit falls from the plant (or is eaten by animals) and the seeds are introduced into the dirt. So pick early, pick often, and enjoy those beautiful tomatoes!
Now that you know what to do this season to keep your tomato plants healthy, maximize your tomato harvest, and enjoy the most flavorful varieties out there, I’ll wish you good gardening. Get out there, get your hands dirty, breathe in that delightful smell unique to tomato plants, and enjoy a bountiful harvest!