Spring planting is often filled with hope and excitement, visions of a bountiful harvest and plans for what you will do with all of your extra garden produce. But does summer have you feeling discouraged as you wait for a harvest that is slow or nonexistent?
Don’t lose hope! If you’ve got zucchini not producing or tomato plant flowers but no fruit, here is a quick list to help you diagnose what your problem might be. Remember, gardening is often about trial and error… Even if some problems are too late to fix this season, you will be better equipped to succeed next season!
Not enough sunlight
Plants that produce fruit (as opposed to herbs and leafy greens) need an average of at least 6-8 hours of sunlight per day. If yours don’t get this much, they may look healthy but will probably not give you much in terms of harvest. If your plants look “leggy” or lanky (stretching tall to search for light), and produce flowers but no fruit, this is another clue they might be lacking sunlight.
Too much water
One of the most common reasons for a tomato plant not producing fruit is too much water. Some plants, like tomato plants, will be slow to produce if they are given too much water. If you have tomato plants not producing even though the plants are large, leafy, and beautiful, this might be your problem. Try cutting back a bit on how much you water, or watering less often. This will signal to the plants that they need to produce their offspring (fruits) to create the next generation of plants before their conditions become less favorable. For more info on how watering affects your plants, see this post.
Incorrect fertilizing or poor soil
At the beginning of the season, plants need a good amount of nitrogen (the first of the three numbers on a fertilizer container) to get started and produce lots of leafy growth. Later in the season, though, phosphate or phosphorus (the second fertilizer number) becomes more important since it helps produce root and fruit growth. If you are still using a fertilizer that is highest in nitrogen, this may be why your plants are producing gorgeous leafy growth instead of fruit. Add some higher phosphate fertilizer instead. Just be sure not to over-fertilize (too much non-organic fertilizer can burn your plants). Read more about choosing and applying fertilizer here.
Even proper fertilizer can’t fix bad soil, though. Soil is the most important part of your garden! If you are planting in the ground, your soil most likely needs some sort of organic matter tilled in–compost, manure, or bagged garden soil. This helps the roots get the air and drainage they need, and provides some fertilizer as well.
Temperatures aren’t right
If you have had an unusually hot or cold spell, some plants’ production may be affected by this. For instance, it’s common to have tomatoes not setting fruit well if temperatures are colder or hotter than the range they prefer. Warm season vegetables will need consistent warm temps, and cool season crops will not like too much heat.
If temperatures are a common challenge in your area, you should consider choosing plants that are listed as heat tolerant or cold tolerant. Also be sure that you are planting the right crops at the right time of year—don’t plant fall vegetable crops in the summer, for instance.
They aren’t mature enough
If it seems like everyone else is getting a good harvest, but your plants are not producing yet, it may be that you planted later than they did. Each plant has a typical “days to harvest” length, which usually means it needs to be planted in your garden a certain number of days before the fruit will mature. If you plant late, sometimes applying a good fertilizer right away can help your plants catch up, but sometimes it’s still a matter of waiting until the maturity date.
If it’s getting close to the maturity date but your plants seem small, they may need a boost of balanced fertilizer. This is one of the most common reasons for zucchini not producing or squash shriveling on the vine–squash plants need plenty of fertilizer. For tips on choosing a fertilizer, go here.
Especially if your area has a short growing season, like mine, it is a good idea to choose plant varieties with shorter “ days to maturity” or “days to harvest” range. This is usually listed on their label. Counting out that number of days from when you transplanted them into your garden will usually give you the best idea of when to expect a harvest (starting out with bigger more mature plants might mean earlier harvest, but not necessarily).
Not enough pollinators in the garden is (hopefully) a less common problem, but it still happens. If you rarely see any bees in your yard or around your plants, there are a few solutions you can try. If you have lots of squash blooms but no fruit,
If possible, consider what pesticides your yard and area are exposed to, if they harm bees, and how you can minimize exposure. If you have a gardener or pest control company, ask what products they use. You can find information a few effective organic bee-safe products for your garden here.
Consider planting some flowers that attract bees. A quick internet search or visit to a garden center can give you some ideas for your area (you will often find plants or flower seed mixes marked “attracts bees and butterflies”).
If this doesn’t work, it is possible to find vegetable or ideas that don’t need insect pollination. Cavili squash is one variety that doesn’t.