Gardening Tip of the Week

Nearly Time to Harvest Sweet Potatoes

September 30

If you planted sweet potato slips back in the spring or early summer, this is the time to start checking to see when to harvest sweet potatoes. You can harvest sweet potatoes whenever they are the size you want. If you see some tubers sticking out of the ground, dig a few up to see if they are big enough. If they are too small check back in a few weeks. If your sweet potatoes are ready to harvest. Make sure to harvest during dry conditions using a digging fork in a wide circle around where the plants enter the ground. Try to avoid damaging the sweet potatoes. Once harvested sweet potatoes will need to be cured. The curing will heal any scrapes, sweeten the tuber, and dry it allowing them to store longer. To cure sweet potatoes keep them in a sunny spot that is warm, and has plenty of airflow. It will take about 1-2 weeks for them to fully cure. Remember to save one or two for starting slips in the spring!

Last chance to plant seed crops in 2019!

September 9th

This week is the last chance to get most seed crops in the ground. Most cool-season vegetables will take two months to get good harvests, especially due to shorter day lengths and cooler temperatures. Vegetables with short harvest times (radish, lettuce, mustard greens) will be a good choice, as well as root crops (carrots and parsnips) that can be mulched or covered with a cold frame and protected from freezing weather. Spinach and salad mix can be sown for another few weeks.   To keep your plants alive during the winter you should think about using a cold frame to protect them frosts. Usually, you will put the cold frames on the plants right around the first frost date of October 22nd.  When using cold frames, check the high temperature for the day. If it is a sunny day above 65 degrees make sure to open up the top of the frame to prevent overheating the plants.

Loose-leaf salad mix that you can plant this week so you can get a few harvests before winter

Hornworm in the Garden

September 3rd

The time is ripe to begin spotting the dreaded tomato hornworm in your garden. The caterpillar’s distinctive green stripes and sheer size make it more noticeable than other pests you might find in your garden. Though it is blends in with tomato plants and often hard to find. The best way to spot them is look for whole branches that have had all the leaves eaten off. The hornworm may not necessarily kill your plant, but because it eats the leaves it can create conditions ripe for sunscald. If you notice eggs on its body, a beneficial wasp has parasitized it, and is best left alone. Otherwise, pulling them off by hand or using a BTK product should limit the problem.

A tomato hornworm with wasp eggs on its back. If they look like this leave them be!

More Fall Planting – Succession Planting

August 26

 Head lettuce planted 2 weeks apart

We are currently in the middle of the fall planting season in Missouri.  Most of the longer growing plants such as kale, collards, broccoli, cabbage should be in the ground now or this week.

For faster-growing veggies, you can plant fall until early-mid September and they will get big enough before the days become too short. With that in mind, you may want to try succession planting your fall crops. Succession planting is the technique of planting the same crop over multiple weeks instead of all at once which will give you a continuous harvest of the crop. Succession planting is done from seed and the best crops are beets, carrots, radishes, turnips, lettuce, and spinach.  The best way to start is to figure out everything you are going to plant for the fall season and then break it into quarters or thirds and plant that quarter or third every week. This technique is also great in the school garden. You can have students seeing plants at different stages of growth at the same time. If you are thinking about testing out succession planting try starting out with radishes. They are quick-growing, easy to germinate, and don’t take up much space!

The Time to Plant for Fall is Now!

August 19

Even though it is still definitely summer, now is the best time to plant your cool-season plants. Fall Planting is almost identical to spring planting except you need to about 10 days to the Days to Maturity on the seed packets.  This is because as we get farther into fall plants slow their growth as we get less and less sunlight. The longer growing plants such as carrots, kale, collards, broccoli, and beets should all be put into the ground now. You can wait a few weeks to a month to start planting radishes, turnips, spinach, and lettuce (but you can plant some now too). When looking at plants to grow this fall look for the varieties with the shorter Days To Maturity (DTM) and those that have some frost tolerance. For example here at Gateway Greening, we grow a faster-growing Cabbage called Caraflex that gets to full maturity about 10-14 days before most other cabbages. Make sure to keep your fall plants well-watered, add plenty of straw or leaf mulch around them, and if possible give them shade.

Harvesting and Curing Garlic

July 2, 2019

If you planted garlic last fall right about now is when it should be time to harvest. There may be a difference of a few weeks based on what variety of garlic you planted. 

When figuring if it is time to harvest garlic take a look at the leaves. There isn’t a perfect measurement to tell when garlic is finished, but usually, when about half the leaves on your garlic plants are brown and dried out they are close to being ready.  If they are at the stage you should stop watering them for about a week before harvesting. This will dry out the garlic and let them store longer. After that week pull all of the garlic, it should be as simple as pulling the plants out of the ground, but if not then use a trowel or something to loosen the soil around the plant, making sure not to nick any of the garlic bulbs.  After they are all out brush off the excess dirt but do not wash the garlic after you harvest it.  Any extra moisture in the bulb will cause the garlic to rot.

What garlic looks like after being cured for about 1 month

Any garlic that you won’t use right away you will need to “cure”. Curing will dry out and enhance the flavor of the garlic.  You will need to put your garlic in a shady, dry place that gets lots of air circulation. There will be a strong garlic smell so it is best to have them outside. At Gateway Greening we tie ours in bunches and hang them under our pavilion. If you can’t hang them, laying them on a table or somewhere that won’t get wet will suffice. Make sure to check on them every couple days to see if any are rotting and toss those ones out.  After the month the leaves will be completely brown and dried and the roots will be stiff. The leaves and roots can be cut back to about ½ inch. Don’t forget to save the biggest bulbs of garlic so that you can plant them this fall!

Onions: Good For More than Just Eating

March 26, 2019

There is a lot of questionable information and old wives tales circulating about companion planting. Some pairings work well in very specific circumstances and not in others and sometimes the science behind successful pairing is not well-documented. However, one of the tried-and-true is planting onions among or around your other crops to deter pests – insects and rabbits. The strong scent of onions can drive off some pests and it will disguise the scent of other crops.

Even if you are not terribly interested in onions as a crop themselves, they are easy to grow interspersed with other crops. And they store well once harvested.

There are a couple of ways to grow onions – they can be started from seed indoors in late winter or direct sown outdoors in early spring. You can sometimes find seedlings to plant as well.

However, the easiest and most common is onion sets, which are young onion bulbs grown from thickly sown seeds (the plants were not given enough room to grow full-size onions). These can be re-planted and with adequate space, they will grow into full-size onions. Plant the sets with the point is just below the top of the soil and space them about 4-6 inches apart (or vary depending on what you are planting next to). Like most root crops, onions like a soil that is consistently moist.

Time to Start Peppers and Eggplant

February 27, 2019

It is time to sow hot and sweet peppers and eggplant seeds indoors. Both of these plants are slow growers that like heat and do not tolerate cold temperatures. Starting them indoors now means the plants will be a nice size for transplanting when nighttime temperatures are consistently above 55ºF (usually beginning of May)

Both Eggplants and Peppers are thirsty plants but do not like to be waterlogged, so we recommend using trays or pots with drainage holes and a separate water tray. Before planting, be sure to wash trays with hot water and soap, sanitize with a 9 parts water, 1 part bleach solution to prevent last year’s pests from causing disease this spring. Fill with a seed starter mix or use peat pellets. It is important to have a well draining soil mixture. If the soil is too heavy you can have mold growing on your seedlings! Keep growing medium moist, but not wet!

Eggplants and Peppers also like warm soil, so set your tray on a propagating mat or on top of the refrigerator to encourage germination. Once sprouted, give the peppers plenty of light (cool fluorescent lamps as close to the tray without touching the plant).

When transplanting them outside both eggplants and peppers need full sun and about 18″ of space per plant. Avoid planting peppers and eggplants in places where tomatoes grew last year as the three are susceptible to the same diseases.

Getting Your Tools Ready for Spring

February 13, 2019

We are getting close to Spring so this is the time to check the conditions of your tools. Make sure they are clean, sharp, and in good working order.

While tools should be cleaned after every use and particularly before winter storage, sometimes one gets missed. Start with clean tools. If any tools are cracked or broken, asses whether they can be fixed or need to be replaced. If there is any rust on functional tools, sand the rust spots off with 80 grit sandpaper, a wire brush, or, for extensive rust, a drill with a wire brush attachment.

If your tools need sharpening, brace the tool and use a simple mill file. Draw it at an angle across the edge you want to sharpen in one direction, in one smooth stroke along the length of the edge, maintaining the angle of the factory bevel (cutting edge) until you’ve achieved the desired sharpness.

With cleaned and rust-free (or as close as you can get) tools, wrap up the chore by oiling the exposed metal with boiled linseed oil.

Low Tunnels and Cold Frames

February 6, 2019

You can get a jumpstart on spring planting by putting up a low tunnel or cold frame.Putting them up now will warm the soil several weeks early and allow your cool season vegetables to germinate. They will continue to protect seedlings from freezing temperatures and sun scald as we head out of winter and can also be used to harden off the seedlings started indoors.

Low tunnels are simple to construct and many different ways to do them. The way we normally do them is using PVC pipe.  To build them – Attach pipe straps – found in the plumbing section of the hardware store – to the outside of your bed. Bend small diameter PVC pipe (keep it warm until you are ready to bend it in place – cold PVC will snap!) and slide them into the pipe straps. Then cover with clear plastic sheeting. The heavier the plastic the better, it will stand up to UV light and protect from cold temperatures. However, heavier plastic also lets less light in, which leads to slower growth. Greenhouse film is the the best type of plastic sheeting.

A cold frame can be constructed out of scrap lumber and an old window (avoid using windows with frames with lead paint). Construct a box from the lumber and add the window to the top with hinges so you can vent the cold frame on bright, sunny days. Ideally, the window slopes and you position the frame so the slope is south-facing in order to get the most sun exposure.

Even more simply, a cold frame from an old window and straw bales. Arrange the bale so the window rests on top. When the weather warms, remove the window and use the straw bales to mulch the garden.
Do remember that on bright, sunny days, even quite cold ones, temperatures inside cold frames and low tunnels can climb high enough to stress plants. They need to be vented during the day and sealed up as night approaches and temperatures drop.