Indoor seed starting: update and tips for success

by Mark Levisay

It’s been two weeks since I planted my first seeds indoors under my new LED lights and I thought I’d give a quick update on  the progress so far.  Basically all of the seeds have germinated, though I’m still hoping to see a couple more vincas show up that haven’t poked through yet.  I planted three varieties of lettuce and they were the fastest to germinate-all in 4-6 days.

A 6-pack of lettuce seedlings.  The two on the left are “New Red Fire” and already show some of their red coloration.

Since they germinate quickly they are also the first to display the adult leaves.  I am pleased to see that the seedlings are growing low to the soil and in a very compact manner.  This indicates that my new lights are giving them plenty of light for optimal growth.  In dim light the seedlings would be tall and spindly, growing toward whatever light they could find.

Starfighter leaf lettuce seedling.

Now that the lettuce have started to produce their adult leaves I’ll begin to fertilize them, since the seed starter soil doesn’t contain any fertilizer of its own.  This week I’ll add a small amount of a liquid soluble fertilizer (ex. Miracle Gro) to my watering can, and water the lettuce plants with that.  I won’t begin to fertilize the pepper or vinca seedlings until they start to display their adult leaves.

Two pepper seedlings.

The peppers and vinca seeds took almost two weeks to germinate, though some started to appear about ten days after planting. I usually plant two seeds in each starter cup, and as you can see in the photo, both have germinated.  I’ll wait about a week, until all of the seedlings have emerged, and then thin the seedlings, leaving the strongest one in each cup.

Vinca seedlings.

Unlike the peppers, when I have two vinca seedlings in a cup, I’ll let both seedlings grow.  These plants won’t grow nearly as big as the pepper plants, and my wife will either plant the resultant “twin” as it is or split them at planting time.

If you’ve planted multiple seeds in your starter cups, and a few haven’t come up, this is a good time to move some around.  I use a pocket knife to dig a narrow but deep hole in the empty cup, and then “prick out” one of the multiple seedlings from another cup.  Insert the seedling’s long tap root down into the hole, press the soil in around it, and water well.  This way you can have at least one seedling in each cup.

Now that we’re at the mid-point of February, it’s time to start thinking about planting brassica seeds for planting out in the garden in early April.  Cabbage and broccoli seeds germinate quickly, but will take 4-6 weeks to mature indoors.  Then plan for a week of hardening off outside before actually planting in the garden.

March is the time to start tomatoes, basil and peppers

It’s still not time yet to plant warm season seeds like tomatoes and basil, or most peppers.  Early March is a good time to plant pepper seeds, as they take almost 2 weeks to germinate and about 6 weeks to mature indoors.  Basil is similar, though they germinate more quickly but take longer to mature.  Tomatoes germinate in a week or less, but still require 4-5 weeks of indoor growth before hardening off.  Start those seeds in mid-March, with a goal of having them hardened off and planted in the garden around the middle of May, after our average last frost date.

Any questions, e-mail me at marklevisay@gmail.com  Good luck!

Starting seeds indoors

by Mark Levisay

In spite of the snow we’ve had recently this is a good time to think about starting garden seeds indoors.  You may have a favorite variety of a vegetable or flower you can’t normally find at a garden center and planting them from seed may be your only option.  Generally you can get a wider range of varieties of plants available in seed form, so learning to start them indoors is a good idea.  It may take anywhere from six to eight weeks for the seedlings to be ready to harden off (more on that later) and germinating time might be up to two weeks, though many are much faster.  Now is the time to plant seeds for plants you want ready for the garden in early April-things like broccoli and cabbage.  Peppers and tomatoes can wait until March.

There aren’t too many things you’ll need to start seeds indoors, but good lights are probably the most important.  Few homes have large south facing windows which might provide enough natural light for seed germination and growth.  Better to invest in bright artificial light that you can place anywhere that you have space for a table.  Today LED lights are probably your best bet, as they are lightweight, bright, use little electricity and last a long time.  They usually are available in daylight spectrum light which is optimal for plant growth.  In my last blog I detailed making my new three fixture LED which is 4’ long and can cover four “flats” of plants.  If you don’t have that much room a 2’ long fixture would cover one flat and that might be all you need.  You’ll want to hang them about 6-9” above the soil level of the pots you’re using and then be able to raise them as your plants grow.

You can use any kind of tray or pot for starting seeds as long as it has drainage and has been disinfected.  You shouldn’t have to clean newly bought pots, but if your pots have been used before clean them thoroughly with a mixture of 1 part bleach to 10 parts water and let dry before filling with soil.

Two types of plastic “6-packs” used for seed starting.  The larger fit 6 to a flat, where the smaller go 12 to a flat.

Currently I’m using the larger sized cups for plants that will be under the lights for quite a while.  Later on I’ll use the smaller cups for things like tomatoes and peppers that will germinate and go outside pretty quickly.  I also use a large flat tray under my plant flats to keep excess water from pouring onto the floor.  This tray actually came from under the air handler in my heat pump system.  This had cracked and needed to be replaced.  I rescued and re-purposed it for plant duties.  Any other flat, rimmed tray will work, or even an old towel placed on your table under the flats.

The soil you use in your plant pots is important—you don’t want it to contain any real nutrients for the plants and most general potting soils contain slow release fertilizer.  Instead, use seed starter potting soil specifically designed for the job.  Espoma, Jiffy, and Miracle Gro all sell these.  I’ve had trouble wetting the Jiffy Mix thoroughly, so I usually use the Miracle Gro Seed Starter mix. Espoma is a good option if you are looking for an organic product. If you do buy the Jiffy Mix, put it in a bucket and soak it in water until it is thoroughly wet.  Squeeze out the excess water before filling your pots.  Never let the soil dry out, as it can be hard to re-wet, and seeds need constant moisture to germinate.  You won’t need to add fertilizer until after the seedlings get their first set of adult leaves, and at that point you can use a liquid soluble general purpose fertilizer when you water.

Labels are really important, especially if you’re growing several varieties of the same plant, as all of the seedlings will look the same, and it’s easy to get confused.  Some of the plastic 6-packs will come with plastic labels, but you can also make your own.  Popsicle sticks, tongue depressors or even strips of cardboard will do.  If you re-use them from year to year it’s a good idea to disinfect them with your 10-1 bleach solution.

Now let’s go through the procedure I use to plant the seeds.  First, I fill the cleaned 6-packs with seed starter soil, level to the tops.

6-packs filled with dry seed starter soil

My second step is to put the packs in the driveway and water them with a watering can to thoroughly soak the soil.

6-pack after watering

You’ll note that the watering process compacts the soil slightly in the cups, giving you space to add seeds.

Next I’ll bring those wet 6-packs back in the house and put them under the lights, which at this stage really help you see what you’re doing!  I label the 6-packs, or even the rows within them, and then place seeds into the cups.  I generally put 2 seeds in each cup, and later thin out one if both germinate.  With some flowers I let 2 plants grow and then separate them when planting.  Press the seeds down lightly so that they make good contact with the wet soil.

6-pack with labels and pepper seeds

Next, I’ll cover the seeds with a small amount of the seed starter mix and water it.  Some seeds need light to germinate (for example coleus and statice) so check your seed packs for specific instructions.  Seeds only need to be covered to about their own thickness, so this isn’t much soil and I use a spray bottle rather than a watering can, as the spray disturbs the seeds less.

6-pack with seeds covered, and spray bottle ready for the next step.

Now for the waiting, as some seeds can take up to two weeks to germinate.  Keep them moist at all times.  Some people cover the moist flats with “Saran” plastic wrap to hold in the moisture.  Some seed trays will come with clear plastic covers used to keep in moisture.  I just use my spray bottle multiple times each day to keep the soil moist.  Once the seeds germinate  you can switch back to watering in a more conventional manner.  Use the light from dawn to dusk, but don’t run them 24 hours a day.  Keep the trays in a warm but not hot area of your home.  I keep my house at 68F and have never had a problem.  I have also started to use an oscillating fan on the other side of the room to simulate nature’s breezes, as I think this makes the plant stems stronger.

My light table set up with a flat of planted and watered seeds.

Once the plants are up you may need to raise the lights so that you’re always 6-9” above the tops of the plants.  When the plants have grown for a while, they’ll start to look more like the ones you might see on sale at The Corner Store.  Now it’s time to “harden off” which is the process of acclimatizing the plants to the great outdoors.  Place them outdoors in a shady area, and each day give them a few hours of sun, increasing the amount each day for a week or until they’re in full sun.  Keep them well watered, as the little plants are not used to this outdoor stuff.  If it looks like rain you may want to put them under cover, as often a heavy rain will knock over the young plants.

Give this a try, and before you know it the process will be second nature.  If you have any questions please e-mail me at marklevisay@gmail.com.  Good luck!

Building a LED seed starting light

Last fall I decided to re-build my seed starting light using brighter and more energy efficient LED lights.  My original light consisted of two 2-bulb 48” fluorescent “shop light” fixtures hanging in a wooden frame with chains so the height of the lights could be adjusted.  Each February, I set up a folding table and position the light frame on top to begin seed starting for the year.

This set up had always worked well, though the fluorescent bulbs seem to dim with time, and then pose a disposal hazard due to the mercury inside them.  Using modern LED lights promised a reduction in energy use and a long life span.  I ordered a set of four Freelicht brand 45W, 4500 Lumen, 5000K (daylight balanced) 2 bulb 48” LED light fixtures from Amazon.com which cost about $75.  Once they arrived I immediately installed one fixture in my workshop to see how it worked.  I was pleased to find the fixtures light in weight and obviously brighter than the fluorescent light they replaced.

My original light hanging frame, made from 1x2” lumber is 53” long and 36” high, plenty of room for the 48” light fixtures and space for 4 standard plant flats. The frame sits on top of a folding table I set up each February for the seed starting season.

Now, how to link together the three light fixtures?  The lights each come with 2 short cables with an eye on one end and hook on the other, which made it easy to install the fixture to the rafters in my workshop.  The lights also are built with a typical “keyhole” for mounting on a screw flush to a surface on each end, and I decided to try this route.

The 48” lights each come with a cord, pullchain style switch and a receptacle to allow lights to be linked together.

I cut two pieces of 1x2” lumber into 22” lengths and carefully measured the center of each, and then 9” on either side.  I drilled pilot holes and then inserted #8 x1” wood screws into the holes, leaving just enough space to be able to insert the screwheads into the light fixtures.

The 48” lights each come with a cord, pullchain style switch and a receptacle to allow lights to be linked together.

To keep the light fixtures from sliding around and falling off the screws I used clear silicone sealant as an adhesive to “glue” the light fixtures to the boards.  The silicone is not a super strong adhesive, so I can break the bond and change the light spacing later if I need to.

Closer look at the silicone holding the board in place on the light fixture.

Once the silicone adhesive has set up I was able to turn the light assembly over and attach 2 eyehooks to the top center portion of the boards.  This will allow me to attach the lights to my hanging frame with two lightweight chains.  The chains allow the light to be lowered or raised depending on the size of the growing plants.

Three light assembly with eyehooks ready for hanging.

Now for the finished product!  When I mounted the three light fixtures to the boards, I made sure to reverse the middle fixture so that two of them could be plugged into each other.  This allows just one light to be plugged into the plugstrip on the hanging frame, and I can use the plugstrip switch to control all three lights at once.  The only final adjustment I had to make was to add 2 large washers to the top of one light fixture as balancing weights to get the overall setup to hang level.

Finished light assembly hanging in frame and all lit up!

Now I will set up my folding table and I’ll be ready to start some seeds!  I usually start my first seeds indoors on Groundhog’s Day (2/2), so it won’t be long.  Next time I’ll write about the details of that process, what seeds I start that early in the year, and give you an update on how the new lights are working out!

Any questions feel free to contact me at marklevisay@gmail.com.

Tomatoes in Central Virginia, Part 3: Growing tips

by Mark Levisay

Now that you’ve got your tomato plants in the ground, how do you care for them to ensure maximum fruit production?  I have found there are several things you can do throughout the growing season to help your plants thrive.

Tomato plants tied to support poles as they grow.

Provide great support

The first thing is to give the plants good support to keep them off the ground and growing vertically.  I use 8’ 2x2” poles to support my plants, though cages can work as well.  Using strips of old sheets or pillowcases I tie the growing leaders to the poles at least every week.  An interval of 4-8” is probably good-more supports will help hold up heavy sets of fruit.  I usually tie just under a node, which is where a leaf comes off the plant’s stem.  Don’t tie them too tight, as the stems will get bigger over the summer and you don’t want to prevent the flow of nutrients up the stems to the leaves and fruit.

Continue tying all summer long, at least until the plant gets to the top of the poles!  The goal here is to keep the plants away from soil splash during heavy rains, as that can infect the plant with fungal spores present in the soil.  The ties and supports also prevent damage from summer storms.

Prune regularly

Secondly we want to prune the plant and train it to grow with two or three main “leaders,” which get tied up to the support.  Tomatoes want to produce many growing shoots and will produce “suckers” at almost every node.  These shoots will produce flowers and fruit if allowed to grow, but the root system will have trouble supporting all of these stems and the plant will be very thick with foliage. 

We also want to encourage air movement within the tomato patch and help more sunlight reach the fruit so it can ripen.  When the plant is 12-18” tall you will notice one or two of the suckers will be really big and robust.  I let one or two grow in addition to the main leader and remove all other suckers that emerge.

A good rule of thumb is to pinch off any suckers on the plant each time you tie the new growth up or roughly once a week.  You’ll even notice suckers that appear where you’ve already pinched one off but remove it again if it appears.  This pruning actually stimulates the plant’s vertical growth which will aid with air movement and sun exposure.

Fertilize strategically

Fertilizing your plants is really important as tomatoes are classed as heavy feeders.  I use Plant Tone organic fertilizer when I plant the seedlings.  Once the first fruit has set, about 2 weeks before your first ripe fruit is expected, fertilize each plant with a fertilizer relatively high in nitrogen (N).  After that, at one month intervals, feed the plant a fertilizer that is higher in Phosphorus (P) as that will help support the flowering and fruit production.  Remember, if you are growing indeterminate plants they will continue to grow, flower and produce fruit until killed by frost or disease.

Keep it clean

To prevent the spread of disease it’s also important to practice good hygiene in your tomato patch.  I generally consider any yellow or brown leaves I see to be diseased and remove them as soon as I can.  Not only remove them from the plant, but from the garden as well.  I don’t even put them in my compost pile, as the fungal spores can survive for up to 5 years in compost or soil, unless your compost pile is really achieving the high temperature needed to kill them (131F for 3 days). 

When in doubt, throw them out!  Your plants will start to look bare at the bottom, but that won’t affect the fruit production if they’re actively growing at the top.  At the end of the season, when your tomato plants are dead, remove all of the old leaves and stems from the garden, and try to plan for having your tomatoes in a different area next year.  Most farmers practice crop rotation, and you should too.

Good luck!

Have a garden question? Send me an email at marklevisay@gmail.com.