Q & A
Got a gardening question? Ask Susan! What follows are the 20 most recent reader questions. Each time a new one comes in, I’ll add it to the top. To ask a question, drop me a note at Susan@susansinthegarden.com.
To view the Q&A by topic, click on one of the following links:
Critters
Flowers
Fruit
Insects
Miscellaneous
Vegetables
Q: Our covers (and hoops) on the raised beds were no match for the snow. Did your new thicker row covers work? If so, could you please let us know where you got them? JB
A: We have 2 raised beds with hinged lids that are covered with agricultural insect netting. They have done well so far for 2 reasons: 1) The hinged lids are quite strong, and 2) In November, we secured a layer of plastic over the outer tops of each hinged lid so that most of the snow would slide off of them. The hinged raised bed lid is a do-it-yourself project from my book, The Vegetable Garden Pest Handbook. The agricultural insect netting came from a company that used to be called AgFabric.com, but they changed their name to GardenPort.com a few months ago. Here is a link to their insect netting options and sizes: https://www.gardenport.com/collections/insect-netting. We have been extremely happy with the insect netting so far. This will be its second season in our garden and I feel pretty confident that it should do equally well this year. It kept out aphids, cabbage butterflies, and leafminers with no problems at all. If you haven’t seen my video where I compared the different types of covers we’ve used, here’s a link to it: https://www.youtube.com/watch?v=uhDRiLX5070
Q: What is going on with our maple trees that despite the cold temperatures, wind, snow, freezing rain, etc., the leaves are not
dropping off? MB
A: The simple explanation is that our weather essentially went from an extended period of summer weather (which was awfully nice) right into wintry weather at the beginning of November. Because of this, our deciduous trees and shrubs didn’t have a chance to go through their normal process of shedding their leaves, which normally occurs as early to mid-fall temperatures slowly decrease. The base of each leaf, where it attaches from its stem to the tree or shrub, has a layer specialized cells known as the abscission layer. As temperatures drop in the fall, they start to deteriorate, which means the leaves separate from the plant and drop to the ground. In the 40+ years I’ve lived in Spokane, I have never seen anything like what we’re experiencing now! And it’s all because we didn’t go through that normal transition period (a.k.a. autumn) between summer and winter. We have lost a lot of branches from our hawthorn tree and other trees, as well as from the shrubs. It’s so frustrating and discouraging. And our fruit trees are completely covered leaves! I keep thinking that now that the weather is slightly milder, they’ll all get down to business and drop their leaves. To be honest, I really don’t know what to expect when spring gets here, but I sure hope the old leaves will have dropped by then.
Q: Where can I find the design and the build out of your hoop house? RS
A: My husband Bill designed it and we built it together, way back in 2014. I documented the supply list and how we built it in a blog post. There’s even a video that shows the construction part of the project.
Q: I meant to ask you how your winter-sown plants did this year (that you did a video about in January)? JA
A: Overall, the winter-sown seedlings did quite well. I think one of the main reasons I like the winter sowing method is because I can start
additional seeds without taking up precious space underneath our grow
lights. The only seeds that didn’t germinate (no idea why!) were the white
strawflowers. Maybe those didn’t care for that method? But the rest
germinated really well. The plants that did well were the ‘Stuttgarter’ onion seeds, love in a
mist, milkweed and Queen Anne’s Lace ‘Dara’. Since we really tend to focus most of our seed-starting time and
resources on edible crops, that’s why I mostly started flower seeds with the winter sowing method. I intend to use that method again in Jan. or Feb.
Q: We have beautiful tomatoes ripening in our garden… but almost all of them have brown, discolored bottoms… is this heat damage? Is it safe to cut off the brown discolored areas and eat the remaining tomato? We really hate to have to throw away all of these beautiful tomatoes! RSG
A: I’m so sorry to hear about your tomatoes. They have what is called blossom-end rot. It isn’t a disease but it’s caused by insufficient watering, esp. during hot spells. I have a video on this very topic that will explain exactly what it is. And yes, you can trim off the brown spots and eat the rest… as long as there isn’t any black mold present.
Q: Do you have any advice on getting my harvested potatoes to store better?
A: We use a large Rubbermaid-type plastic storage container and partially fill it with lightly-moistened straw. We don’t wash off the potatoes after harvesting them, but we usually place them in a wheelbarrow in a dark area for about a day after harvest. That dries any soil that is stuck onto the potatoes, to where most of it falls off. Place the potatoes into the bin and put the bin in a dark, cool area… we usually store them in our unheated (but insulated) garage during the fall and winter months. The potatoes keep so much longer, and without shriveling up and getting rubbery, with this method! I have a video on both harvesting and storing potatoes, so you might want to watch it for more details.
Q: I planted sugar baby watermelon, Crenshaw melon, wax beans, and collard seeds in compostable seed starter trays. The kind of seed starter trays that can be planted with the seedling. The collard seedlings emerged May 8. However, none of the other seeds are showing any signs of growth. I take the collard seedlings outside daily for approximately 6 or more hours of daylight. Previously, I would also take the other seed starter trays outside. However, now I only take the collard seedlings outside in the daylight and bring them inside before sunset. I no longer take any of the other starter trays outside. I keep them indoors under grow lights and I placed a slightly warm heating pad underneath them with a thick towel between the heating pad and the starter trays. Also, I use a spray bottle to mist tops of them when they are dry. What can I do to get these seeds to grow?? Thank you for any assistance.
A: The watermelons, melons and beans are all warm-season crops that need to get off to a warm start. If you were putting their seed-starter trays outdoors prior to their germination, it may have been too cool for them to sprout… even though I realize you’re in a warmer hardiness zone. Also, did you use a humidity dome (or clear plastic bag) on the trays to help with germination? That always makes a big difference. Once the majority of seeds have sprouted in each tray, that’s when you take off the dome or bag for each of them. Since you mentioned needing to mist the tops of the starter trays, that makes me thing you weren’t using a dome or bag. (Follow-up from Susan: she wasn’t using a humidity dome or bag, so plans to start doing that. Between the warmer indoor environment and the increased humidity, I’m hopeful her seeds will sprout soon)
Q: We would like to know what is the best soil to use for filling our 22 feet by 5 feet by 2 feet (6 cubic yards) raised bed. We need a local source where we can pick it up ourselves to save hauling fee. We are looking for organic soil… Have you had any experience with any of the local nurseries? JM
A: It is tricky getting just the right kind of soil for new beds. Here in Spokane, your best bet is to go with a local landscape supply business such as Gibson’s Nursery, Bark Boys, and Wittkopf Landscape Supply. Let them know what you need the soil for. The important thing is to pay them a visit so you can look at what they would like to sell to you. It is just about impossible to find organic soil (unless something has changed since I last looked) and organic would be the best route, esp. for edible crops. But these landscape supply companies carry “Barr-Tech” compost which is decent quality. You’ll be looking for something called “premium garden soil” that has a bit of compost mixed in. You don’t want 100% compost because that will be too rich. And you don’t want something that is really sandy because the water will run through it. No matter what you choose, I think it’s really important to add in some organic materials such as grass clippings from a lawn that hasn’t been treated with herbicides such as Weed ‘n Feed, shredded leaves, and/or compost (even partially decomposed will work). And if you can get your hands on earthworms from another area of your garden, plunk them in, too! I have always found that garden soil from landscape companies tends to be a bit on the sterile side, so the more organic materials you can mix in, the better. I would avoid adding horse manure as it can contain a persistent herbicide that will taint your soil for several years before it finally dissipates. You might also consider adding some worm castings and azomite. I don’t know if you’re familiar with Joe Lamp’l but he has a blog post on his site in which he lists his perfect raised bed soil recipe.
Q: Just bought two 8×10 cedar raised beds and have some good 50/50 soil mix. Was wondering if it’s best to plant my 4 strawberry plants (starts that my daughter divided from her garden) directly in my raised bed or in a container of some sort? Wasn’t sure if they would take over too much space in my raised beds? Also I’m not sure when I can put my plants outside. Right now I just have them in the house near a window. DS
A: I’m afraid the strawberry plants would definitely spread throughout your raised bed because it’s in their nature to send out lots of runners. I think your best bet would be to grow them in a container where you would have more control over them. You should be able to plant them outside in a week or two (mid- to late April).
Q: I pick up my tomato plants from a local nursery. I usually do that on May 5th. They come in 2″ pots. Last year – they were rootbound by the time I put them in my raised beds on May 30th. So this year – I wanted to put them in larger pots. I have a few questions for you: 1) I have some 4″ and 6″ pots. Can I put them in there? Can I do it right away or should I wait until I harden them off? 2) After I harden them off – I keep the plants outside from 6AM – 5PM and then I put them in the garage (I live in an apartment, so I don’t want to leave them outside overnight). 3) Do I need to set up a grow light in the garage to give them additional light? If yes – how much time would I need to keep them under the lights and how far above the plants should they be? 4) Should I water my plants with fish emulsion until I put them in the garden (is once a week good?)
A: Here are my answers: 1) Yes, both of those pot sizes would work, but with 6″ being better. I would do it right away. Start your hardening-off process at least a couple of weeks before transplanting the tomato seedlings into your raised beds. Just a little time here and there, so they are really hardened-off nicely. 2) It doesn’t sound like you have a question here, but I think that sounds fine. 3) Re: grow light, the plants could use maybe 4 more hours of light if it’s convenient. If it isn’t, just keep an eye on the plants to see how they’re doing. The lights should be 2-4″ at most above the tops of the plants. 4) I start feeding my plants with diluted fish emulsion once they have a few true leaves. I repeat the feeding about every 2 weeks. I also give them one or 2 more feedings after they’ve been transplanted into the garden. Then I stop, or you can feed them with a fertilizer that is high in phosphorus (the middle number on fertilizer packages). What I usually do is add some bone meal to the bed prior to transplanting my tomato seedlings because it is organic and high in phosphorus. Be sure to follow the label directions for any soil amendments you use.
Q: I have repotted my tomato seedlings and they looked great. They are indoors and about 12 inches under a grow light. They are about 4 inches tall and I water about once a week. I started to notice the leaves curling and the falling off on most of them. I didn’t see any insects on them but I am worried I’m going to lose them all. None of my other seedlings are having this problem. Do you have any suggestions? LM
A: Wow, that is a rather unusual problem. Here are some thoughts: 1) The grow light should be 2-4″ (at most) above the tops of the plants. 2) Are the plants getting enough water, or too much water? Either could cause leaves to curl and fall off. The potting medium should be lightly moist, not sopping wet and not dry as a bone. 3) Have you been giving the seedlings fertilizer every now and then? I typically start giving a liquid nitrogen fertilizer (such as Alaska Fish Fertilizer) to seedlings once they have a few true leaves. And about every 2 weeks. Be sure to follow the label directions to the letter.
Q: I’m hoping you can give me advice about aphids. Each year I plant lots of red & yellow petunias in Spokane and at our cabin. In each pot I replace 1/2 the old soil with new potting soil. For the last 2 years my petunias grow beautifully and about mid-August I see the plants changing. I can see aphids on the plants. I have sprayed with water, soap water & aphid spray. Because my pots get so full & overflowing it’s almost impossible to spray everywhere. Eventually my plants look terrible. After doing some reading I am wondering if aphid eggs live in the soil through the winter. If so, what can I do? It would cost a fortune to start over with new soil. Before I plant is there something I can treat the soil with and keep the aphids from hatching, if that is the case? Thanks and I would appreciate any advice you can give me. JS
A: That is so odd about your aphid problem and it certainly sounds like you have tried just about everything. However, you are correct that the aphids are probably coming from previously-used potting soil. At the end of each growing season, female aphids mate and then lay eggs on plant debris. The eggs overwinter and hatch in the spring. So I believe that’s why you’re ending up with so many aphids each year. I’m glad to know that you are using organic methods because that is so important. Especially when it comes to dealing with aphids, because pesticides will also kill beneficial insects. And there are so many beneficials that love to feast on aphids! So you don’t want to inadvertently kill the good bugs. I don’t know of anything you could put into the potting soil to kill the aphids. I do know that some folks sterilize their potting soil by baking it in the oven, but I’ve heard it smells AWFUL! So you probably won’t want to go that route. Good luck.
Q: I don’t remember if I should harden off leeks, onions and my gutter peas before I plant them.
All my starts are still inside. If I start moving them in and out now, do you think I can plant in a week? And should I provide row cover protection if frost is imminent? I am growing the Bulgarian Giant leeks for the first time and following what you are trying this year. They are about 10 inches tall and I did not prune back either, as you suggested. They are in cells and I hope I can separate the multiples that are in some cells. I always grab my Walla Walla sweet onion starts as soon as they come in to the garden center. This year I put them in an empty cell tray with a sprinkle of soil and water. JM
A: Yes, I would definitely start the hardening-off process today for each of those crops. The weather for the next few days looks kind of atrocious so you’ll have to monitor that. But I just planted my leek seedlings yesterday. I decided to cover their bed, not so much due to the weather but more because our quail friends have a penchant for pulling up onion seedlings. I believe onion and leek seedlings don’t need hardening off as much as plants with regular leaves. And they are more tolerant of cooler temperatures, but it never hurts to be careful! Re: the peas, I’m going to plant mine in the next few days. I intend to give them a bit of floating row cover for protection — again, partly due to the quail and also because of the low temps.
Q: We’re so intrigued by the new agricultural insect netting you have over your lettuce bed in your 2022 #11 video. We understand you’re
still testing it but we would like to try it too in the meantime. Can
you give us the product name and source for that? MD
A: I have been asked this question so many times now! We purchased the garden insect netting from Agfabric.com. It comes in different sizes and widths. It’s my understanding that they are selling out of some of the smaller sizes, but here is a link to the type of netting we bought. If you can’t find what you need, try Agriculture Solutions. Before you order any, be sure to calculate the width by measuring from the ground, up and over your hoops and back down to the ground on the other side!
Q: I’ve been meaning to ask you if I need to feed my starts with a fertilizer. I’ve planted them with Johnnys seed starting mix, and some have been in several weeks, but aren’t very big. SD
A: I definitely recommend feeding your plant starts because once they use up the energy stored in their seeds, they are essentially “running on empty.” I like to use a liquid high-nitrogen fertilizer such as Alaska Fish Fertilizer or another type of seedling booster fertilizer (Espoma has some nice products). When the seedlings are young, it’s best to mix up a weaker fertilizer solution. For example, if the label calls for 1 tbsp. of fertilizer to a gallon of water, I use 1/2 tbsp. to a gallon of water instead. I also fertilize the seedlings when I transplant them out into the garden, and again about 2 weeks later.
Q: I think I recall in one of your videos (either in the video or in the comments) you mentioned a pellet that you sprinkled to protect plants from being nibbled by rabbits. I searched your book and your website, but I
couldn’t find it. Do you remember the product you suggested? DH
A: I’m trying to remember any videos where I sprinkled a product to protect my plants and I’m pretty sure I was talking about keeping gophers and voles away from the flowers in my front bed. And that product is goes by different names such as Mole Chaser and Mole Away. It’s made with woody granules that are coated with caster oil. Unfortunately, that doesn’t work for rabbits. First of all, when trying to repel any type of critter from eating your plants, what you use depends upon whether the plants are ornamental or edible. So always read the label to see if it’s safe to use around edibles… if that’s what you’re in need of. The good news is that there are some commercially-made repellents that keep rabbits away from plants. Again, check the label to see their specific use. I haven’t had any experience using them, however, so I can’t really recommend a specific product from personal experience. However, I should mention that Plant Skydd makes a rabbit repellent. I’m not sure if it’s OK to use near edible crops so you’ll want to check that. Other possible options are to place bars of deodorant soap near plants (not touching, if they’re edible crops), or scaring them with pinwheels or a motion-activated sprinkler. Barriers are the most effective method for keeping rabbits away… whether it’s with a chicken wire structure, bird netting, or with a wire fence around the area you need to protect.
Q: I have a question about corn. I bought a few different varieties, I know they are all bicolor hybrid, such as peaches and cream, but I was wondering if they are planted next to each, will I get cross pollination? SW
A: Corn does cross-pollinate very easily so I would recommend only planting a single variety this year… unless you want some surprises!
Q: Have you ever used spinosad, which I understand is approved for organic gardening? I’ve used it to successfully stop codling moths in my apple trees, and I see on the label that it can also stop leafminers. It would sure be nice not to have to mess with floating row covers, but I wonder if, even though it’s approved for organic gardening, it would make the chard and beet tops unsafe to eat. What do you think? TM
A: We have primarily used spinosad on our apple trees. But yes, it can be used for other types of things, including certain vegetable crops. However, I think leafminers are difficult to control with a spray because the larvae are located in between the layers of cells in plant leaves (primarily beefs, spinach and Swiss chard) which gives them a bit of protection. So I would much rather use floating row covers because they act as a physical barrier that prevents the adult fly from laying eggs on the leaves in the first place. I’ll always choose a row cover (when appropriate for the problem), rather than a spray… even organic sprays. To answer your other questions: yes, spinosad is an organic product that is made from fermented soil bacterium. The label should state how many days you need to wait, in between spraying the leaves and harvesting them.
There are two things about spinosad that makes me hesitant to use it, however: 1) it will kill pollinators so you have to time the spray when they’re not active, and 2) research has shown that insects are able to develop a resistance to it. That means you wouldn’t want to use it repeatedly, but rather alternate it with other products. But again, I prefer using floating row cover. Aside from in our orchard, we don’t use any organic sprays at all.
Q: My rhodendron needs help. It does not look good heading into fall and winter.
The leaves on my rhody are green but they are are curled lengthwise as though the plant is dry. the plant is not dry. The plant is south facing under a large maple tree. I am not sure what is going on. My other nearby rhody is looking very healthy. BB
A: I’m not sure where you live but one of the main reasons rhododendron leaves curl is drought conditions. So if you are in the PNW region like I am, or in another part of the country where you’ve experienced heat and drought, that is likely the cause. I would recommend making sure it’s well-watered going into the winter and hopefully it will bounce back by next spring.
Q: for the second year we have grown a Brandywine heirloom tomato in a large container in our garden. Both years, the tomatoes developed cracks radiating out from the stem that split, then start to spoil. Last year, the greenhouse said it was due to calcium deficiency, this year I used an organic fertilizer with calcium and go the same development. The plant is on a drip so it doesn’t get foliage watering. The fruit doesn’t seem impacted other than the spoilage after the cracks split. KF
A: Tomatoes tend to crack due to water issues. Sometimes it happens after it rains because the tomato swells a bit and the skin isn’t stretchy enough to accommodate that. It can also happen when plants don’t get enough water. I believe there are some varieties that are a bit more prone to splitting and cracking. Here is some additional information: What causes tomatoes to crack.
Q: I got some lovely tall morning glory (blue) vines going (started from seed) but have had absolutely not blossoms or flowers! My friend hasn’t either. What is going on this summer? Is it because of the heat? Just thought I’d ask. KA
Q: What bird feed do you usually use in your bird feeders. I know some are better than others, and that some leave less
mess underneath. RF
Any suggestions? DB
A: The rain gutter method, I cover the ends of the gutters by taping cardboard onto them. So the potting soil doesn’t fall out of the gutters, but the excess moisture can escape. I don’t drill holes into the bottoms of the rain gutters for this reason, and also because when I first plant seeds in the gutters, they are sitting on a piece of plastic inside our sliding glass door! So I don’t want my floor to get wet. When you mention how the seeds rot before they germinate, are you saying this happens when you start them indoors? If so, you are correct in that the soil must be way too wet. So you’ll want to address that if you try this method (or any other way of starting them indoors, for that matter). The seed-starting mix or potting soil should be lightly moist, not sopping wet.
I even consulted with the EPA and their site states it is safe around edible plants. Refer to question #8 at this link: https://www.epa.gov/mosquitocontrol/bti-mosquito-control.
You mentioned about adding soil to beds: if you’ve found that the soil has really compacted down, it’s a good idea to add additional soil if that is an option. And you can do that now or in very early spring (but now is preferable). If you have to leave the beds bare over the winter months, that is perfectly OK. Sometimes we just don’t have time in the fall to get around to these things. I would definitely not cover the beds because you want them to get the benefit of moisture from rain and snow.
A: I mostly purchase microgreens seeds from sproutpeople.org and
trueleafmarket.com. The latter carries the 10″ square planting flats,
ones with drainage holes and ones without (I use the former and place
them into heavy-duty seedling flats that don’t have holes. Those came
from our local garden center. My light set-up is from Gardener’s Supply (gardeners.com) and the
specific one I have is the Stack & Grow system. You can buy a single
level, 2 levels or 3 altogether. It depends on how much seed-starting
you’ll be doing and how much room you need. Mine has LED lights which
are more energy-efficient.
(to view older questions and answers, go to the topic links at the top of the page; I intend to archive the older questions there since they are all great questions!)